Axle assembly having a resolver and a method of assembly

ABSTRACT

An axle assembly having a resolver and a method of assembly. The axle assembly may include an electric motor module that may be mounted to a differential carrier. The electric motor module may have a motor cover that may be disposed opposite the differential carrier. The resolver may be mounted to a side of the motor cover that may face away from a rotor.

TECHNICAL FIELD

This disclosure relates to an axle assembly that has a resolver and amethod of assembly.

BACKGROUND

An axle assembly having an electric motor module is disclosed in U.S.Pat. No. 8,858,379.

SUMMARY

In at least one embodiment, an axle assembly is provided. The axleassembly may include a differential carrier, an electric motor module,and a resolver. The electric motor module may be mounted to thedifferential carrier. The electric motor module may include a motorhousing, a stator, a rotor, and a motor cover. The stator may be fixedlydisposed in the motor housing. The rotor may be received in the statorand may be rotatable about an axis. The motor cover may be mounted tothe motor housing opposite the differential carrier and may be spacedapart from the differential carrier. The resolver may be mounted to aside of the motor cover that may face away from the rotor.

In at least one embodiment, a method of assembling an axle assembly maybe provided. The method may include assembling an electric motor moduleto a differential carrier. The electric motor module may include a motorhousing, a stator, and a rotor. A resolver may be mounted on a side of amotor cover that may face away from the rotor. The motor cover may bemounted to the motor housing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an axle assembly.

FIG. 2 is a section view of the axle assembly along section line 2-2showing a shift collar in a first position.

FIG. 3 is a section view of the axle assembly showing the shift collarin a second position.

FIG. 4 is a section view of the axle assembly showing the shift collarin a third position.

FIG. 5 is a magnified view of a portion of FIG. 2

FIG. 6 is a magnified view of a portion of FIG. 2.

FIGS. 7-20 are exploded views of the axle assembly.

FIG. 21 is a section view of a portion of an electric motor module ofthe axle assembly along section line 21-21.

FIG. 22 is a magnified section view of an example of a spigot bearingassembly that may be provided with the axle assembly.

FIG. 23 is a schematic representation of the axle system that includesthe axle assembly and a control system.

FIG. 24 is a magnified section view of a portion of the axle assemblythrough a tone ring that is disposed on a planet gear carrier and anassociated speed sensor.

FIG. 25 illustrates a planetary gear set that may be provided with agear reduction module.

FIG. 26 is a magnified view of a portion of FIG. 25.

DETAILED DESCRIPTION

As required, detailed embodiments of the present invention are disclosedherein; however, it is to be understood that the disclosed embodimentsare merely exemplary of the invention that may be embodied in variousand alternative forms. The figures are not necessarily to scale; somefeatures may be exaggerated or minimized to show details of particularcomponents. Therefore, specific structural and functional detailsdisclosed herein are not to be interpreted as limiting, but merely as arepresentative basis for teaching one skilled in the art to variouslyemploy the present invention.

Referring to FIG. 1, an example of an axle assembly 10 is shown. Theaxle assembly 10 may be provided with a motor vehicle like a truck, bus,farm equipment, mining equipment, military transport or weaponryvehicle, or cargo loading equipment for land, air, or marine vessels.The motor vehicle may include a trailer for transporting cargo in one ormore embodiments.

Referring to FIGS. 1 and 23, the axle assembly 10 may provide torque toone or more traction wheel assemblies that may include a tire 12 mountedon a wheel 14. The wheel 14 may be mounted to a wheel hub 16 that may berotatable about a wheel axis 18.

One or more axle assemblies may be provided with the vehicle. As is bestshown with reference to FIGS. 1 and 2, the axle assembly 10 may includea housing assembly 20, a drive pinion 22, an electric motor module 24, agear reduction module 26, a shift mechanism 28, a differential assembly30, and at least one axle shaft 32.

Housing Assembly

Referring to FIG. 1, the housing assembly 20 may receive variouscomponents of the axle assembly 10. In addition, the housing assembly 20may facilitate mounting of the axle assembly 10 to the vehicle. In atleast one configuration, the housing assembly 20 may include an axlehousing 40 and a differential carrier 42.

The axle housing 40 may receive and may support the axle shafts 32. Inat least one embodiment, the axle housing 40 may include a centerportion 50 and at least one arm portion 52.

The center portion 50 may be disposed proximate the center of the axlehousing 40. The center portion 50 may define a cavity that may receivethe differential assembly 30. As is best shown in FIG. 2, a lower regionof the center portion 50 may at least partially define a sump portionthat may contain a first lubricant. Splashed lubricant may flow down thesides of the center portion 50 and may flow over various internalcomponents of the axle assembly 10 and gather in the sump portion. Thesump portion may be part of a first lubricant chamber as will bediscussed in more detail below.

The center portion 50 may include a carrier mounting surface 56. Thecarrier mounting surface 56 may facilitate mounting of the differentialcarrier 42 to the axle housing 40. For example, the carrier mountingsurface 56 may face toward and may engage the differential carrier 42and may have a set of holes that may be aligned with corresponding holeson the differential carrier 42. Each hole may receive a fastener, suchas a bolt, that may couple the differential carrier 42 to the axlehousing 40.

Referring to FIG. 1, one or more arm portions 52 may extend from thecenter portion 50. For example, two arm portions 52 may extend inopposite directions from the center portion 50 and away from thedifferential assembly 30. The arm portions 52 may have substantiallysimilar configurations. For example, the arm portions 52 may each have ahollow configuration or tubular configuration that may extend around andmay receive a corresponding axle shaft 32 and may help separate orisolate the axle shaft 32 or a portion thereof from the surroundingenvironment. An arm portion 52 or a portion thereof may be integrallyformed with the center portion 50. Alternatively, an arm portion 52 maybe separate from the center portion 50. In such a configuration, eacharm portion 52 may be attached to the center portion 50 in any suitablemanner, such as by welding or with one or more fasteners. An arm portionmay rotatably support an associated wheel hub 16. It is alsocontemplated that the arm portions 52 may be omitted.

Referring to FIGS. 1 and 2, the differential carrier 42, which may alsobe called a carrier housing, may be mounted to the center portion 50 ofthe axle housing 40. The differential carrier 42 may support thedifferential assembly 30 and may facilitate mounting of the electricmotor module 24. As is best shown with reference to FIGS. 2, 7 and 14,the differential carrier 42 may include one or more bearing supports 60,a mounting flange 62, and a bearing support wall 64.

Referring to FIGS. 7 and 14, the bearing support 60 may support a rollerbearing assembly that may rotatably support the differential assembly30. For example, two bearing supports 60 may be received in the centerportion 50 and may be located proximate opposite sides of thedifferential assembly 30. The bearing support 60 may be provided invarious configurations. For example, a bearing support 60 may include apair of legs that extend from the differential carrier 42. A bearing capmay be mounted to the legs and may arch over a roller bearing assemblythat may rotatably support the differential assembly 30. As anotherexample, the bearing support 60 may be received in a roller bearingassembly which in turn may support the differential assembly 30.

The mounting flange 62 may facilitate mounting of the electric motormodule 24. The mounting flange 62 may be configured as a ring that mayextend outward and away from a first axis 70 and may extend around thefirst axis 70. The mounting flange 62 may include a set of fastenerholes 72. The fastener holes 72 may be spaced apart from each other andmay be threaded in one or more configurations. Each fastener hole 72 maybe configured to receive a fastener 74 that may secure the electricmotor module 24 to the mounting flange 62 as will be discussed in moredetail below. In at least one configuration, the mounting flange 62 mayinclude an abutment surface 76 and a locating ring 78.

The abutment surface 76 may face toward the electric motor module 24, orto the right from the perspective shown in FIG. 3. In at least oneconfiguration, the abutment surface 76 may be disposed substantiallyperpendicular to the first axis 70. The abutment surface 76 may bedisposed closer to the first axis 70 than the locating ring 78.

The locating ring 78 may be configured to receive a portion of theelectric motor module 24 as will be discussed in more detail below. Thelocating ring 78 may extend around the first axis 70 and may protrudefrom the abutment surface 76. For instance, the locating ring 78 mayextend in an axial direction that may extend away from the axle housing40. The locating ring 78 may include or define a ring end surface 80 andan inner ring surface 82.

The ring end surface 80 may be axially offset from the abutment surface76. For example, the ring end surface 80 may be disposed further fromthe axle housing 40 than the abutment surface 76. In at least oneconfiguration, the ring end surface 80 may be disposed substantiallyperpendicular to the first axis 70 and may be configured to engage amotor housing of the electric motor module 24 as will be discussed inmore detail below.

The inner ring surface 82 may extend from the abutment surface 76 to thering end surface 80. For instance, the inner ring surface 82 may extendfrom the abutment surface 76 to an end of the ring end surface 80. Theinner ring surface 82 may face toward the first axis 70 and may extendaround and may receive at least a portion of a coolant jacket of theelectric motor module 24 as will be discussed in more detail below.

Referring to FIGS. 2 and 7, the bearing support wall 64 may supportbearings that may rotatably support other components of the axleassembly 10. For example, the bearing support wall 64 may supportbearings that may rotatably support the drive pinion 22, bearings thatmay rotatably support a rotor of the electric motor module 24, or both.The bearing support wall 64 may extend in an axial direction away fromthe axle housing 40 and may extend around the first axis 70. As such,the bearing support wall 64 may define a hole 90 that may receive thedrive pinion 22 and various other components as will be discussed inmore detail below. In addition, the bearing support wall 64 may beradially positioned between the first axis 70 and the electric motormodule 24. The bearing support wall 64 may be integrally formed with thedifferential carrier 42 or may be a separate component that is fastenedto the differential carrier 42.

Referring to FIGS. 5 and 7, the exterior side of the bearing supportwall 64 that faces away from the first axis 70 may have a steppedconfiguration that may generally become narrower as the distance fromthe axle housing 40 increases. Such a configuration may include a firstcircumferential surface 100, a second circumferential surface 102, and athird circumferential surface 104.

The first circumferential surface 100 may extend around the first axis70 and may face away from the first axis 70. The first circumferentialsurface 100 may support a first rotor bearing assembly as will bediscussed in more detail below.

The second circumferential surface 102 may be axially positioned betweenthe first circumferential surface 100 and the third circumferentialsurface 104. The second circumferential surface 102 may have a smallerdiameter than the first circumferential surface 100.

The third circumferential surface 104 may be axially positioned betweenthe second circumferential surface 102 and an end surface 106 of thebearing support wall 64. The third circumferential surface 104 may havea smaller diameter than the second circumferential surface 102. Thethird circumferential surface 104 may support a second rotor bearingassembly as will be discussed in more detail below.

A groove 108 may be provided in the third circumferential surface 104.The groove 108 may extend toward the first axis 70 and may be axiallypositioned between the second circumferential surface 102 and the endsurface 106. The groove 108 may receive a retainer, such as a snap ring,as will be discussed in more detail below.

Drive Pinion

Referring to FIG. 2, the drive pinion 22 may provide torque to a ringgear 110 that may be provided with the differential assembly 30.Moreover, in an axle assembly that includes a gear reduction module 26,the drive pinion 22 may operatively connect a planetary gear set of thegear reduction module 26 to the differential assembly 30. The drivepinion 22 may extend along and may be rotatable about the first axis 70while the ring gear 110 may be rotatable about the wheel axis 18. Inaddition, the drive pinion 22 may extend through the hole 90 in thebearing support wall 64 and through a hole in a motor cover as will bediscussed in more detail below. In at least one configuration, such asis best shown with reference to FIGS. 2, 9 and 16, the drive pinion 22may include a gear portion 120 and a shaft portion 122.

The gear portion 120 may be disposed at or near an end of the shaftportion 122. The gear portion 120 may have a plurality of teeth that maymate with corresponding teeth on the ring gear 110. The gear portion 120may be integrally formed with the shaft portion 122 or may be providedas a separate component that may be fixedly disposed on the shaftportion 122.

The shaft portion 122 may extend from the gear portion 120 in adirection that extends away from the axle housing 40. As is best shownwith reference to FIGS. 9 and 16, the shaft portion 122 may include afirst outer surface 130, a second outer surface 132, a third outersurface 134, a fourth outer surface 136, a threaded portion 138, and aspline 140.

Referring to FIGS. 5, 9 and 16, the first outer surface 130 may extendfrom the gear portion 120 and may be an outside circumference of aportion of the shaft portion 122. A first drive pinion bearing 150 maybe disposed on the first outer surface 130 and may rotatably support thedrive pinion 22. The first drive pinion bearing 150 may have anysuitable configuration. For instance, the first drive pinion bearing 150may be configured as a roller bearing assembly that may include aplurality of rolling elements 152 that may be disposed between an innerrace 154 and an outer race 156. The inner race 154 may extend around andmay be disposed on the first outer surface 130. The outer race 156 mayextend around the rolling elements 152 and may be disposed on thebearing support wall 64 of the differential carrier 42 and may bereceived in the hole 90 of the bearing support wall 64.

The second outer surface 132 may be axially positioned between the firstouter surface 130 and the third outer surface 134. The second outersurface 132 may be an outside circumference of a portion of the shaftportion 122 and may have a smaller diameter than the first outer surface130. One or more spacer rings 160 may be disposed on the second outersurface 132. The spacer rings 160 may be disposed between the innerraces of the drive pinion bearings to inhibit axial movement of thedrive pinion bearings toward each other.

The third outer surface 134 may be axially positioned between the secondouter surface 132 and the fourth outer surface 136. The third outersurface 134 may be an outside circumference of a portion of the shaftportion 122 and may have a smaller diameter than the second outersurface 132. A second drive pinion bearing 170 may be disposed on thethird outer surface 134 and may rotatably support the drive pinion 22.The second drive pinion bearing 170 may have any suitable configuration.For instance, the second drive pinion bearing 170 may be configured as aroller bearing assembly that may include a plurality of rolling elements172 that may be disposed between an inner race 174 and an outer race176. The inner race 174 may extend around and may be disposed on thethird outer surface 134. The outer race 176 may extend around therolling elements 172, may be disposed on the bearing support wall 64 ofthe differential carrier 42, and may be received in the hole 90 of thebearing support wall 64. The inner race 174 of the second drive pinionbearing 170 may have a smaller inside diameter than the inner race 154of the first drive pinion bearing 150. The outer race 176 of the seconddrive pinion bearing 170 may have a smaller outside diameter than theouter race 156 of the first drive pinion bearing 150.

The fourth outer surface 136 may be axially positioned between the thirdouter surface 134 and the threaded portion 138. The fourth outer surface136 may be an outside circumference of a portion of the shaft portion122 and may have a smaller diameter than the third outer surface 134.

A seal support ring 180 may be disposed on the fourth outer surface 136.The seal support ring 180 may extend around the first axis 70 and mayhave a hole 182 that may receive the drive pinion 22. Moreover, the sealsupport ring 180 may engage and may facilitate sealing against thefourth outer surface 136 to help separate the axle assembly 10 intofirst and second lubricant chambers as will be discussed in more detailbelow. The seal support ring 180 may engage the inner race 174 of thesecond drive pinion bearing 170 and may support one or more seals aswill be discussed in more detail below.

The threaded portion 138 may be axially positioned between the fourthouter surface 136 and the spline 140. The threaded portion 138 mayfacilitate installation of a pre load nut 190.

The preload nut 190 may be threaded onto the threaded portion 138 andmay secure the seal support ring 180 to the drive pinion 22. The sealsupport ring 180 may be axially positioned between the inner race 174 ofthe second drive pinion bearing 170 and the preload nut 190. The preloadnut 190 may apply a preload force on the first and second drive pinionbearings 150, 170 via the seal support ring 180. As is best shown inFIG. 5, a portion of the seal support ring 180 may overhang and mayextend around the preload nut 190 and may be configured to support aseal as will be discussed in more detail below.

The spline 140 may be disposed between the threaded portion 138 and anend of the shaft portion 122 that may be disposed opposite the gearportion 120. The spline 140 may include a plurality of teeth. The teethmay be disposed substantially parallel to the first axis 70 and may matewith a corresponding spline on a shift collar of the shift mechanism 28as will be discussed in more detail below. Alternatively, the teeth ofthe spline 140 may mate with a corresponding spline of a rotor outputflange that may couple the drive pinion 22 to a rotor of the electricmotor module 24 when the gear reduction module 26 and shift mechanism 28are omitted.

Electric Motor Module

Referring to FIG. 2, the electric motor module 24 may be mounted to thedifferential carrier 42 and may provide torque to the differentialassembly 30 via the drive pinion 22. The electric motor module 24 may beprimarily disposed outside the differential carrier 42. In addition, theelectric motor module 24 may be axially positioned between the axlehousing 40 and the gear reduction module 26 and the axle housing 40.Main components of the electric motor module 24 are best shown withreference to FIGS. 7, 8, 11, 14, 15 and 18. In at least oneconfiguration, the electric motor module 24 may include a motor housing200, a coolant jacket 202, a stator 204, a rotor 206, a first rotorbearing assembly 208, a second rotor bearing assembly 210, a rotorbearing preload module 212, and a motor cover 214.

Referring to FIGS. 2, 7, 14 and 21, the motor housing 200 may extendbetween the differential carrier 42 to the motor cover 214. For example,the motor housing 200 may extend from the mounting flange 62 of thedifferential carrier 42 to the motor cover 214. The motor housing 200may extend around a first axis 70 to define a motor housing cavity 220.The motor housing cavity 220 may have a generally cylindricalconfiguration. The motor housing 200 may extend continuously around andmay be spaced apart from the bearing support wall 64 of the differentialcarrier 42. In at least one configuration, the motor housing 200 mayhave an exterior surface 222, an interior surface 224, a first endsurface 226, a second end surface 228, a set of fastener holes 230, andone or more ports 232.

The exterior surface 222 may face away from the first axis 70 and maydefine an exterior or outside surface of the motor housing 200.

The interior surface 224 may be disposed opposite the exterior surface222. The interior surface 224 may be disposed at a substantiallyconstant radial distance from the first axis 70 in one or moreconfigurations.

The first end surface 226 may extend between the exterior surface 222and the interior surface 224. The first end surface 226 may be disposedat an end of the motor housing 200 that may face toward the differentialcarrier 42. More specifically, the first end surface 226 may be disposedadjacent to the mounting flange 62 of the differential carrier 42. As isbest shown in FIG. 21, the first end surface 226 may engage the ring endsurface 80 of the locating ring 78 of the differential carrier 42.However, the motor housing 200 and the first end surface 226 may not bereceived inside the mounting flange 62 of the differential carrier 42.

The second end surface 228 may be disposed opposite the first endsurface 226. As such, the second end surface 228 may be disposed at anend of the motor housing 200 that may face toward and may engage themotor cover 214. The second end surface 228 may extend between theexterior surface 222 and the interior surface 224. In at least oneconfiguration, the second end surface 228 may not be received inside themotor cover 214.

The set of fastener holes 230 may be arranged around the first axis 70and may be aligned with the fastener holes 72 of the differentialcarrier 42. As such, the fastener holes 230 may be spaced apart fromeach other and may be disposed substantially parallel to each other andsubstantially parallel to the first axis 70. Each fastener hole 230 maybetween the first end surface 226 to the second end surface 228. Forexample, the fastener holes 230 may extend from the first end surface226 to the second end surface 228. Each fastener hole 230 may receive afastener 74 that may secure the motor housing 200 to the mounting flange62, the motor cover 214, or both. For example, each fastener 74 mayextend through the fastener hole 230 and may protrude from the first endsurface 226 and the second end surface 228. Opposing ends of thefastener 74 may be threaded. For example, one threaded end may bereceived in the fastener hole 72 of the differential carrier 42 and maymate with the threads of the fastener hole 72 of the differentialcarrier 42. Alternatively, the fastener 74 may extend through thefastener hole 72 of the differential carrier 42 and may be received in anut that may secure the motor housing 200 to the differential carrier42. Similarly, an opposing threaded end of a fastener 74 may mate withthreads of a fastener hole of the motor cover 214 or may extend througha fastener hole in the motor cover 214 and may be received in a nut thatmay secure the motor cover 214 to the motor housing 200.

Referring to FIGS. 7 and 14, one or more ports 232 may extend throughthe motor housing 200. The ports 232 may be configured as a throughholes that may extend from the exterior surface 222 to the interiorsurface 224. The ports 232 may allow coolant, such as a fluid likewater, to flow to and from the coolant jacket 202 as will be describedin more detail below.

Referring to FIGS. 8, 15 and 21, the coolant jacket 202 may help cool orremove heat from the stator 204. The coolant jacket 202 may be receivedin the motor housing cavity 220 and may engage the interior surface 224of the motor housing 200. The coolant jacket 202 may extend axiallybetween the differential carrier 42 and the motor cover 214. Inaddition, the coolant jacket 202 may extend around the first axis 70 andthe stator 204. In at least one configuration, the coolant jacket 202may include a first coolant jacket end surface 240, a second coolantjacket end surface 242, a plurality of channels 244, a first groove 246,a second groove 248, and a coolant jacket cavity 250.

The first coolant jacket end surface 240 may be disposed at an end ofthe coolant jacket 202 and may face toward the differential carrier 42.More specifically, the first coolant jacket end surface 240 may bedisposed outside the motor housing 200 and may be received inside themounting flange 62 of the differential carrier 42. For instance, thefirst coolant jacket end surface 240 may face toward and may contact theabutment surface 76 of the differential carrier 42 and may be receivedinside the locating ring 78.

The second coolant jacket end surface 242 may be disposed opposite thefirst coolant jacket end surface 240. As such, the second coolant jacketend surface 242 may face toward the motor cover 214. The second coolantjacket end surface 242 may be disposed outside the motor housing 200 andmay be received inside a mounting flange of the motor cover 214.

The channels 244 may extend around the first axis 70 and may be disposedopposite the coolant jacket cavity 250. The channels 244 may beconfigured with an open side that may face away from the first axis 70and toward the interior surface 224 of the motor housing 200. Thechannels 244 may be axially positioned between the first coolant jacketend surface 240 and the second coolant jacket end surface 242. Coolantmay be provided to the coolant jacket 202 via a first port 232 and mayexit the coolant jacket 202 via a second port 232. For instance, coolantmay flow from the first port 232 to the channels 244, receive heat fromthe stator 204 as the coolant flows through the channels 244, and exitat the second port 232. A baffle may be provided with the coolant jacket202 that may reverse the direction of coolant flow to help route coolantfrom the first port 232 to the second port 232.

The first groove 246 may be provided in an exterior surface of thecoolant jacket 202 that may face toward the interior surface 224 of themotor housing 200. The first groove 246 may extend around the first axis70 and may be axially positioned between the first coolant jacket endsurface 240 and the channels 244. The first groove 246 may receive afirst seal 260. The first seal 260 may seal against the interior surface224 of the motor housing 200. The first seal 260 may have any suitableconfiguration. For example, the first seal 260 may be configured as anO-ring that may extend continuously around the coolant jacket 202.

The second groove 248 may be provided in the exterior surface of thecoolant jacket 202. The second groove 248 may extend around the firstaxis 70 and may be axially positioned between the second coolant jacketend surface 242 and the channels 244. The second groove 248 may receivea second seal 262. The second seal 262 may seal against the interiorsurface 224 of the motor housing 200. The second seal 262 may have anysuitable configuration. For example, the second seal 262 may beconfigured as an O-ring that may extend continuously around the coolantjacket 202. The first seal 260 and the second seal 262 may cooperate toinhibit or prevent leakage of coolant between the motor housing 200 andthe coolant jacket 202.

The coolant jacket cavity 250 may be defined by the coolant jacket 202.The coolant jacket cavity 250 may be configured as a through hole thatmay extend from the first coolant jacket end surface 240 to the secondcoolant jacket end surface 242 and may be disposed opposite the channels244. The coolant jacket cavity 250 may receive the stator 204.

The stator 204 may be fixedly positioned with respect to the coolantjacket 202. For example, the stator 204 may extend around the first axis70 and may include stator windings 270 that may be received inside andmay be fixedly positioned with respect to the coolant jacket 202, whichare best shown in FIGS. 8 and 15.

The motor housing 200, coolant jacket 202, and the stator 204 may bepreassembled to provide a subassembly that may be assembled othercomponents. An example of an associated assembly sequence is as follows.

First, the coolant jacket 202 may be provided. The coolant jacket 202may include the channels, grooves, and other features previouslydiscussed.

Second, the stator windings 270 may be installed on the coolant jacket202. Installing the stator windings 270 may include positioning thestator windings 270 inside the coolant jacket cavity 250 and against theinside circumference of the coolant jacket 202. The stator windings 270may then be encapsulated or “potted” using any suitable encapsulationmaterial, such as a polymeric material, epoxy resin, or the like.Encapsulation may help electrically insulate the stator windings 270 andmay provide chemical and environmental protection.

Third, one or more seals may be installed on the coolant jacket 202. Forinstance, the first seal 260 may be installed in the first groove 246and the second seal 262 may be installed in the second groove 248. Thefirst seal 260 and the second seal 262 may protrude past the outsidecircumference of the coolant jacket 202 when installed.

Fourth, the coolant jacket 202 along with the stator 204 may beinstalled in the motor housing cavity 220 of the motor housing 200. Themotor housing 200 may be heated to expand or increase the size of themotor housing cavity 220 prior to installation. For instance, heatingthe motor housing 200 may increase the size or inside diameter of themotor housing cavity 220, which may facilitate installation of thecoolant jacket 202 and help avoid displacement of the first and secondseals 260, 262 and/or damage to the first and second seals 260, 262. Thecoolant jacket 202 along with the stator 204, first seal 260, and secondseal 262, may be inserted into the motor housing cavity 220 once themotor housing 200 has been heated to a sufficient temperature or for asufficient period of time to obtain a desired inside diameter.

Fifth the motor housing 200 may be allowed to cool. Cooling the motorhousing 200 may reduce the size of the motor housing cavity 220 and mayfacilitate sealing between the motor housing 200 and the first andsecond seals 260, 262. Accordingly, the interior surface 224 of themotor housing 200 may engage and may compress against the first andsecond seals 260, 262. The motor housing 200 may be sufficiently cooledwhen it reaches ambient temperature or is sufficiently close to ambienttemperature.

Sixth, quality checks may be conducted. Such quality checks may includea leak test and a high potential (“hipot”) withstand test.

The leak test may be conducted to determine whether a leak is presentbetween the motor housing 200 and the coolant jacket 202. For example, apressurized fluid, such as a gas or liquid may be provided via at leastone port 232 to the channels 244. The fluid pressure may be monitored todetermine whether a leak of a sufficient magnitude is present. Forinstance, sealing may be acceptable when the fluid pressure ismaintained for a predetermined period of time.

The high potential withstand test made be conducted to determine whetherthe stator windings 270 are adequately insulated. For example, astandard test voltage may be applied to the stator windings 270 and aleakage current that flows through the insulation or encapsulationmaterial may be monitored. Insulation of the stator windings 270 may beacceptable when the leakage current is less than a predetermined valueor limit. It is contemplated that the leak test and the high potentialwithstand test may be conducted concurrently or sequentially. Forexample, the high potential withstand test may be conducted after theleak test in one or more configurations.

Seventh, the subassembly may be assembled to the differential carrier42. The subassembly may include the motor housing 200, coolant jacket202, the stator 204 and the first and second seals 260, 262. The motorhousing 200 may be placed into engagement with the locating ring 78 ofthe mounting flange 62 of the differential carrier 42 such that thefirst end surface 226 of the motor housing 200 may engage the ring endsurface 80 of the locating ring 78. The first coolant jacket end surface240 may be received inside the locating ring 78 such that the inner ringsurface 82 may extend around a portion of the coolant jacket 202 thatprotrudes from the motor housing 200. Fasteners 74 may be insertedthrough the fastener holes 230 in the motor housing 200 and into thefastener holes 72 of the mounting flange 62 of the differential carrier42 and may be secured as previously discussed.

Eighth, the motor cover 214 may be mounted to and secured to the motorhousing 200. For example, the motor cover 214 may be placed intoengagement with the second end surface 228 of the motor housing 200. Thefasteners 74 may facilitate securing of the motor cover 214. Forexample, the fasteners 74 may extend through corresponding fastenerholes in the motor cover 214. The fasteners 74 may be received in nuts280 that may secure motor cover 214 to the motor housing 200 as is bestshown in FIG. 21.

Referring to FIGS. 2, 8 and 15, the rotor 206 may extend around thefirst axis 70 and may be received inside the stator 204 and the motorhousing 200. The rotor 206 may be rotatable about the first axis 70 withrespect to the differential carrier 42 and the stator 204. The rotor 206may be spaced apart from the stator 204 but may be disposed close to thestator 204. The rotor 206 may include magnets or ferromagnetic materialthat may facilitate the generation of electrical current. The rotor 206may extend around and may be supported by the bearing support wall 64.The rotor 206 may be operatively connected to the drive pinion 22 withor without a gear reduction module 26. For instance, the rotor 206 maybe operatively connected to the drive pinion 22 between the end of thebearing support wall 64 and the motor cover 214, such as with a rotoroutput flange 290 as will be discussed in more detail below.

Referring to FIGS. 5, 8 and 15, the first rotor bearing assembly 208 mayrotatably support the rotor 206. The first rotor bearing assembly 208may receive the bearing support wall 64 of the differential carrier 42and may be received inside of the rotor 206. The first rotor bearingassembly 208 may be axially positioned closer to the axle housing 40than the second rotor bearing assembly 210. The first rotor bearingassembly 208 may have any suitable configuration. For instance, thefirst rotor bearing assembly 208 may include a plurality of rollingelements 300 that may be disposed between an inner race 302 and an outerrace 304. The inner race 302 may extend around and may receive thebearing support wall 64 of the differential carrier 42. For example, theinner race 302 may extend around and may engage the firstcircumferential surface 100 of the bearing support wall 64. The outerrace 304 may extend around the rolling elements 300 and may be disposedon the rotor 206.

The second rotor bearing assembly 210 may be spaced apart from the firstrotor bearing assembly 208. The second rotor bearing assembly 210 may bepositioned closer to the motor cover 214 than the first rotor bearingassembly 208. The second rotor bearing assembly 210 may have anysuitable configuration. For instance, the second rotor bearing assembly210 may include a plurality of rolling elements 310 that may be disposedbetween an inner race 312 and an outer race 314. The inner race 312 mayextend around and may receive the bearing support wall 64 of thedifferential carrier 42. For example, the inner race 312 may extendaround and may engage the third circumferential surface 104 of thebearing support wall 64. The outer race 314 may extend around therolling elements 310 and may be disposed on the rotor 206.

The rotor bearing preload module 212 may be axially positioned betweenthe first rotor bearing assembly 208 and the second rotor bearingassembly 210. In addition, the rotor bearing preload module 212 mayreceive and may extend around the bearing support wall 64. The rotorbearing preload module 212 may exert a preload force on at least onerotor bearing assembly. In addition, the rotor bearing preload module212 may cooperate with various components to help position the rotorbearing assemblies and inhibit axial movement of the rotor bearingassemblies with respect to the bearing support wall 64. In at least oneconfiguration, the rotor bearing preload module 212 may include a firstbearing preload ring 320, a second bearing preload ring 322, and abiasing member 324.

The first bearing preload ring 320 may generally extend around thesecond circumferential surface 102 of the bearing support wall 64. Inaddition, the first bearing preload ring 320 may extend from the firstrotor bearing assembly 208. For example, the first bearing preload ring320 may engage the inner race 302 of the first rotor bearing assembly208 and may be spaced apart from the outer race 304 of the first rotorbearing assembly 208. The first bearing preload ring 320 may be axiallymovable or movable in an axial direction with respect to the secondbearing preload ring 322. In at least one configuration, the firstbearing preload ring 320 may include a center portion 330, a first sideportion 332, and a second side portion 334.

The center portion 330 may be axially positioned between the first sideportion 332 and the second side portion 334. The center portion 330 maybe disposed on the differential carrier 42. For example, the centerportion 330 may have a center portion inner surface 340 that may facetoward the first axis 70 and may engage the second circumferentialsurface 102 of the bearing support wall 64. The center portion innersurface 340 may be disposed substantially parallel to the secondcircumferential surface 102 and may be generally smooth to facilitatesliding axial movement.

The first side portion 332 may extend from the center portion 330 to thefirst rotor bearing assembly 208. For example, the first side portion332 may extend from the center portion 330 to the inner race 302 of thefirst rotor bearing assembly 208. The first side portion 332 may have afirst inner surface 342 that may face toward the first axis 70. Thefirst inner surface 342 or a portion thereof may have a larger diameterthan the center portion inner surface 340. In addition, the first innersurface 342 or a portion thereof may be spaced apart from the bearingsupport wall 64 of the differential carrier 42.

The second side portion 334 may be disposed opposite the first sideportion 332. The second side portion 334 may extend from the centerportion 330 toward the second rotor bearing assembly 210. In addition,the second side portion 334 may extend around part of the second bearingpreload ring 322. As such, the second side portion 334 may be spacedapart from the bearing support wall 64 of the differential carrier 42.

The second bearing preload ring 322 may extend around the secondcircumferential surface 102 and the third circumferential surface 104 ofthe bearing support wall 64. In addition, the second bearing preloadring 322 may extend from the second rotor bearing assembly 210. Forexample, the second bearing preload ring 322 may engage the inner race312 of the second rotor bearing assembly 210 and may be spaced apartfrom the outer race 314 of the second rotor bearing assembly 210. Thesecond bearing preload ring 322 may be stationary and may not move in anaxial direction. In at least one configuration, the second bearingpreload ring 322 may include a bearing contact portion 350 and a guideportion 352.

The bearing contact portion 350 may extend from the second rotor bearingassembly 210. For example, the bearing contact portion 350 may engage orcontact the inner race 312 of the second rotor bearing assembly 210. Inaddition, the bearing contact portion 350 may be disposed on thedifferential carrier 42. For instance, the bearing contact portion 350may engage the third circumferential surface 104 of the bearing supportwall 64. The bearing contact portion 350 may have a smaller diameterthan the guide portion 352.

The guide portion 352 may be at least partially received inside thesecond side portion 334 of the first bearing preload ring 320. Inaddition, the guide portion 352 may extend around and may engage thesecond circumferential surface 102 of the bearing support wall 64. Theguide portion 352 may extend in an axial direction from the bearingcontact portion 350 toward the first rotor bearing assembly 208. Assuch, the guide portion 352 may extend toward the center portion 330 ofthe first bearing preload ring 320. The guide portion 352 may be spacedapart from the center portion 330 due to the biasing force exerted bythe biasing member 324.

The biasing member 324 may bias the first bearing preload ring 320 in anaxial direction with respect to the second bearing preload ring 322. Forexample, the biasing member 324 may exert a biasing force that may biasthe first rotor bearing assembly 208 away from the second rotor bearingassembly 210 away from each other. As is best shown in FIG. 5, thebiasing member 324 may be disposed between the first bearing preloadring 320 and the second bearing preload ring 322. For instance, thebiasing member 324 may extend from the second side portion 334 of thefirst bearing preload ring 320 to the guide portion 352 of the secondbearing preload ring 322.

The biasing member 324 may have any suitable configuration. For example,biasing member 324 may extend around a portion of second bearing preloadring 322, such as the guide portion 352. In such a configuration, thebiasing member 324 may be a spring like a wave spring or a wave washerthat may extend continuously around the first axis 70. Alternatively,the biasing member 324 may not extend continuously around the first axis70. It is also contemplated that multiple biasing members 324 may beprovided. For instance, multiple biasing members 324 such as coilsprings may be arranged at various locations around the first axis 70.

Referring to FIGS. 5 and 15, a first retaining member 360 may bepositioned on an opposite side of the first rotor bearing assembly 208from the first bearing preload ring 320. The first retaining member 360may inhibit axial movement of the outer race 304 of the first rotorbearing assembly 208 toward the axle housing 40. The first retainingmember 360 may be fixedly coupled to the rotor 206 in any suitablemanner. For example, the first retaining member 360 may be received in agroove in the rotor 206. The first retaining member 360 may have anysuitable configuration. For example, the first retaining member 360 maybe configured as a protrusion, such as a snap ring, that may extendtoward the first axis 70. The first retaining member 360 may be spacedapart from the inner race 302. Accordingly, the biasing force exerted bythe biasing member 324 may actuate the inner race 302 with respect tothe outer race 304.

A second retaining member 362 may be positioned on an opposite side ofthe second rotor bearing assembly 210 from the second bearing preloadring 322. The second retaining member 362 may inhibit axial movement ofthe inner race 312 of the second rotor bearing assembly 210 away fromthe axle housing 40. The second retaining member 362 may be coupled tothe differential carrier 42 in any suitable manner. For example, thesecond retaining member 362 may be received in a groove 108 in thebearing support wall 64. The second retaining member 362 may have anysuitable configuration. For example, the second retaining member 362 maybe configured as a protrusion, such as a snap ring, that may extend awayfrom the first axis 70. The second retaining member 362 may be spacedapart from the outer race 314.

Referring to FIGS. 2, 11, 18 and 21, the motor cover 214 may be mountedto the motor housing 200 and may be disposed opposite the axle housing40. For example, the motor cover 214 may be mounted to the second endsurface 228 of the motor housing 200. The motor cover 214 may be spacedapart from and may not engage the differential carrier 42. The motorcover 214 may be provided in various configurations. In at least oneconfiguration, the motor cover 214 may include a first side 370 and asecond side 372. The motor cover 214 may also include a motor coveropening 374 in configurations having a gear reduction module 26.Optionally, the motor cover 214 may include or may partially define oneor more additional features, such as a locating ring 376, a junction box378, an outer ring 380, and a resolver slot 382, and a bearing receivingsurface 384.

Referring primarily to FIGS. 11, 18 and 21, the first side 370 may facetoward the axle housing 40.

The second side 372 may be disposed opposite the first side 370. Assuch, the second side 372 may face away from the axle housing 40.

The motor cover opening 374 may extend between the first side 370 andthe second side 372. The motor cover opening 374 may be a through holethat may extend around the first axis 70.

The locating ring 376 may be configured to receive a portion of theelectric motor module 24. The locating ring 376 may have a similarconfiguration as the locating ring 78 of the differential carrier 42.The locating ring 376 may extend around the first axis 70 and mayprotrude from an abutment surface 390 toward the axle housing 40. Theabutment surface 390 may face toward and may be disposed proximate orengage the second coolant jacket end surface 242 of the coolant jacket202. The locating ring 376 may have a ring end surface 392 that may beaxially offset from the abutment surface 390 and may engage the secondend surface 228 of the motor housing 200. The locating ring 376 mayextend around and may receive a portion of the coolant jacket 202 thatmay protrude from the motor housing 200 toward the first side 370 of themotor cover 214. A plurality of fastener holes 394 may be disposedproximate the locating ring 376. The fastener holes 394 may extend intoor through the locating ring 376. Each fastener hole 394 may be alignedwith a corresponding fastener hole 230 of the motor housing 200 and mayreceive a corresponding fastener 74 as previously discussed.

Referring to FIGS. 11 and 18, the junction box 378 or portion thereofmay be provided with the motor cover 214. The junction box 378 mayextend from the second side 372 and may receive components that mayfacilitate electrical connections to the electric motor module 24. Thejunction box 378 may be integrally formed with the motor cover 214 ormay be provided as a separate component.

The outer ring 380 may extend from the second side 372. The outer ring380 may extend continuously or discontinuously around the first axis 70.The outer ring 380 may provide multiple functions. For example, theouter ring 380 may act as a locating feature that may facilitatepositioning and installation of a shift mechanism housing 900 as is bestshown in FIG. 6. The outer ring 380 may also act as a stop that mayinhibit axial movement of a planetary ring gear 714 of the gearreduction module 26. The outer ring 380 may also facilitate installationof a seal 400, such as an O-ring, that may be extend between the shiftmechanism housing 900 and the motor cover 214. For instance, the seal400 may extend around the outer ring 380 and may be received inside theshift mechanism housing 900.

Referring to FIG. 11, the resolver slot 382 may be disposed between thefirst side 370 and the second side 372 of the motor cover 214. Theresolver slot 382 may be configured as a through hole that may extend tothe motor cover opening 374. The resolver slot 382 may receive a portionof a resolver 600 as will be discussed in more detail below.

Referring to FIGS. 6 and 18, the bearing receiving surface 384 maypartially define the motor cover opening 374. The bearing receivingsurface 384 may extend around the first axis 70 and may extend from ormay be disposed adjacent to the first side 370 of the motor cover 214.The bearing receiving surface 384 may be configured to receive and mayoptionally contact a spigot bearing assembly 410. The spigot bearingassembly 410 may receive the rotor output flange 290 and may helpinhibit deflection of the rotor 206 as will be discussed in more detailbelow. A groove 420 may extend from the bearing receiving surface 384 ina direction that may extend away from the first axis 70. The groove 420may receive a seal 422, such as an O-ring, that may extend around andmay contact the spigot bearing assembly 410. Other mountingconfigurations for the spigot bearing assembly 410 will be discussedafter discussing the rotor output flange 290 in more detail.

Rotor Output Flange

Referring to FIGS. 5, 6, 10 and 17, the rotor output flange 290 mayoperatively connect or couple the electric motor module 24 to the gearreduction module 26. For example, the rotor output flange 290 may couplethe rotor 206 to a sun gear 710 of the gear reduction module 26 as willbe discussed in more detail below. The rotor output flange 290 may befixedly coupled to or fixedly mounted to the rotor 206. As such, therotor output flange 290 may rotate about the first axis 70 with therotor 206. The rotor output flange 290 may be partially disposed insidethe bearing support wall 64 of the differential carrier 42 and may bepartially disposed inside the motor housing 200 and the motor cover 214of the electric motor module 24. In addition, the rotor output flange290 may extend through the motor cover opening 374 of the motor cover214. In at least one configuration, the rotor output flange 290 mayinclude a tubular body 430 and a flange portion 432.

The tubular body 430 may extend around the first axis 70 and may definea rotor output flange hole 434. The rotor output flange hole 434 may bea through hole that may extend along and may be centered about the firstaxis 70. The drive pinion 22 may extend through the rotor output flangehole 434 and may be spaced apart from the rotor output flange 290. As isbest shown in FIG. 6, the sun gear 710 of the gear reduction module 26may be partially received in the rotor output flange 290 and hence maybe partially received in the rotor output flange hole 434. In at leastone configuration, the tubular body 430 may include a rotor outputflange spline 440, an internal groove 442, a first seal support surface444, a spigot bearing support surface 446, a first outer groove 448, arotary disc support surface 450, a second outer groove 452, and a secondseal support surface 454.

The rotor output flange spline 440 may be disposed in the rotor outputflange hole 434. The rotor output flange spline 440 may have teeth thatmay be arranged around the first axis 70 and may extend toward the firstaxis 70. The teeth of the rotor output flange spline 440 may mate with aspline of the sun gear 710 such that the rotor output flange 290 mayrotate about the first axis 70 with the sun gear 710 and the rotor 206.

As is best shown in FIG. 6, the internal groove 442 may be disposed inthe rotor output flange hole 434 and may extend away from the first axis70. The internal groove 442 may be axially positioned between a firstend of the tubular body 430 that may face toward the axle housing 40 andthe sun gear 710. The internal groove 442 may receive a snap ring 460 orother suitable fastener that may help inhibit axial movement of the sungear 710 toward the axle housing 40. Optionally, a spacer 462 such as awasher may be received in the rotor output flange hole 434 and may beaxially positioned between the internal groove 442 and the sun gear 710.

The first seal support surface 444 may extend from the first end of thetubular body 430 to the flange portion 432. The first seal supportsurface 444 may be disposed opposite the rotor output flange hole 434and may be configured to support a seal as will be discussed in moredetail below. The bearing support wall 64 may extend around at least aportion of the first seal support surface 444.

The spigot bearing support surface 446 may be axially positioned betweenthe flange portion 432 and the second end of the tubular body 430. Thespigot bearing support surface 446 may be configured to support thespigot bearing assembly 410 as will be discussed in more detail below.

Referring to FIGS. 6 and 10, the first outer groove 448 may be disposedin the spigot bearing support surface 446 or adjacent to the spigotbearing support surface 446. As such, the first outer groove 448 may bedisposed opposite the rotor output flange hole 434. The first outergroove 448 may extend around the first axis 70 and may extend toward thefirst axis 70. The first outer groove 448 may be axially positionedbetween the spigot bearing assembly 410 and the second end of thetubular body 430. The first outer groove 448 may receive a fastener 464,such as a snap ring, that may engage an inner race of the spigot bearingassembly 410 to inhibit axial movement of the inner race.

The rotary disc support surface 450 may be disposed opposite the rotoroutput flange hole 434 and may be axially positioned between the spigotbearing support surface 446 and the second end of the tubular body 430.In at least one configuration, the rotary disc support surface 450 mayhave a smaller diameter than the spigot bearing support surface 446. Therotary disc support surface 450 may support a rotary disc 466.

Referring to FIGS. 6 and 11, the rotary disc 466 may be fixedly disposedon the rotor output flange 290. As such, the rotary disc 466 may rotateabout the first axis 70 with the rotor 206. The rotary disc 466 may beaxially positioned between the spigot bearing assembly 410 and thesecond end of the rotor output flange 290. As such, the rotary disc 466may be received in the rotor output flange hole 434 and may extendaround the sun gear 710 of the gear reduction module 26. As is bestshown in FIG. 11, the rotary disc 466 may have a non-cylindrical outersurface that may face away from the first axis 70 that may include aplurality of protrusions that may extend away from the first axis 70.The protrusions may be arranged in a repeating pattern around the firstaxis 70.

Referring to FIGS. 6 and 10, the second outer groove 452 may be disposedin the rotary disc support surface 450 or adjacent to the rotary discsupport surface 450. As such, the second outer groove 452 may bedisposed opposite the rotor output flange hole 434. The second outergroove 452 may extend around the first axis 70 and may extend toward thefirst axis 70. The second outer groove 452 may be axially positionedbetween the rotary disc 466 and the second seal support surface 454. Thesecond outer groove 452 may receive a fastener 468, such as a snap ring,that may inhibit axial movement of the rotary disc 466.

The second seal support surface 454 may extend from the second end ofthe tubular body 430 toward the rotary disc support surface 450. Thesecond seal support surface 454 may be disposed opposite the rotoroutput flange hole 434 and may be configured to support a seal as willbe discussed in more detail below.

The flange portion 432 may be disposed between the first end and thesecond end of the tubular body 430. The flange portion 432 may extendfrom the tubular body 430 in a direction that extends away from thefirst axis 70. The flange portion 432 may be fixedly coupled to therotor 206. For instance, the flange portion 432 may include a set ofholes that may be arranged around the first axis 70 and that may receivefasteners 470, such as bolts, that may extend through the holes tocouple the flange portion 432 to the rotor 206. In at least oneconfiguration, the flange portion 432 may include one or moreprotrusions 480.

Referring to FIGS. 5 and 17, the protrusion 480 may extend in an axialdirection toward the rotor 206. In at least one configuration, theprotrusion 480 may be configured as an annular ring that may extendcontinuously around the first axis 70 and around the first seal supportsurface 444. In addition, the protrusion 480 may also extend around thesecond retaining member 362. As is best shown in FIG. 5, the protrusion480 may extend into the rotor 206 and may engage the outer race 314 ofthe second rotor bearing assembly 210 to inhibit axial movement of theouter race 314 away from the first rotor bearing assembly 208. The rotoroutput flange 290 as well as the protrusion 480 may be spaced apart fromthe inner race 312 of the second rotor bearing assembly 210.

Spigot Bearing Assembly

Referring to FIGS. 5, 6, 10 and 17, the spigot bearing assembly 410 mayreceive the rotor output flange 290 and may rotatably support the rotoroutput flange 290. The spigot bearing assembly 410 may help inhibitdeflection of the rotor 206, such as deflection with respect to thefirst axis 70. As such, the spigot bearing assembly 410 may help alignor center the rotor 206 about the first axis 70 and may help improve thestability of the rotor 206 and maintain a desired air gap between therotor 206 and the stator 204. As is best shown with reference to FIGS. 5and 10, the spigot bearing assembly 410 may be received inside the rotoroutput flange hole 434 of the motor cover 214 and may extend between themotor cover 214 and the rotor output flange 290. The spigot bearingassembly 410 may also be axially positioned in the electric motor module24 such that the spigot bearing assembly 410 is received inside of themotor housing 200 and inside of the coolant jacket 202.

Referring to FIGS. 6 and 10, the spigot bearing assembly 410 may haveany suitable configuration. For instance, the spigot bearing assembly410 may include a plurality of rolling elements 500 that may be disposedbetween an inner race 502 and an outer race 504. The inner race 502 mayextend around and may engage the spigot bearing support surface 446 ofthe rotor output flange 290. The outer race 504 may extend around therolling elements 500 and may engage the bearing receiving surface 384 ofthe motor cover 214.

Referring to FIG. 22, an alternative arrangement for supporting thespigot bearing assembly 410 is shown. This arrangement may include anadapter 510 and a spigot bearing biasing member 512.

The adapter 510 may be received in the rotor output flange hole 434 ofthe motor cover 214. For example, the adapter 510 may be configured as aring that may extend around the first axis 70 and may receive the spigotbearing assembly 410. The adapter 510 may also extend around and receivethe spigot bearing biasing member 512. In at least one configuration,the adapter 510 may include a transverse wall 520, a first flange 522,and a second flange 524.

The transverse wall 520 may be radially positioned between the spigotbearing assembly 410 and the motor cover 214. In addition, thetransverse wall 520 may extend generally parallel to the first axis 70.The transverse wall 520 may include a groove 526. The groove 526 may bedisposed adjacent to the second flange 524. The groove 526 may extendaround the first axis 70 and may extend away from the first axis 70.

The first flange 522 may extend from a first end of the transverse wall520 in a direction that extends away from the first axis 70. The firstflange 522 may extend continuously around the first axis 70 in one ormore configurations. The first flange 522 may extend from the transversewall 520 to the motor cover 214. As such, the first flange 522 mayinhibit axial movement of the adapter 510 in a first direction withrespect to the motor cover 214, or to the right from the perspectiveshown in FIG. 22.

The second flange 524 may be disposed opposite the first flange 522. Assuch, the second flange 524 may extend from a second end of thetransverse wall 520. The second flange 524 may extend toward the firstaxis 70 and may extend continuously around the first axis 70. The secondflange 524 may inhibit axial movement of the spigot bearing biasingmember 512 in the first direction. The second flange 524 may be spacedapart from the spigot bearing assembly 410.

The spigot bearing biasing member 512 may be at least partially receivedin the groove 526 of the adapter 510. The spigot bearing biasing member512 may extend from the second flange 524 and may be axially positionedsuch that the spigot bearing biasing member 512 may extend at leastpartially around the fastener 464. The spigot bearing biasing member 512may also be axially positioned between the spigot bearing assembly 410and a resolver 600 that may detect rotation of the rotor 206 as will bediscussed in more detail below.

The spigot bearing biasing member 512 may exert a biasing force on thespigot bearing assembly 410 to inhibit skidding of the spigot bearingassembly 410. Skidding may include sliding motion of the rollingelements 500 rather than rolling motion of the rolling elements 500 withrespect to the inner race 502, the outer race 504, or both. Skidding candisrupt lubricant on surfaces of the spigot bearing assembly 410 andresult in increased operating temperatures, bearing component damage,and reduced service life. The spigot bearing biasing member 512 mayengage the outer race 504 of the spigot bearing assembly 410 and maybias the outer race 504 of the spigot bearing assembly 410 toward thedifferential carrier 42, or to the left from the perspective shown inFIG. 22. This biasing force may preload the spigot bearing biasingmember 512 to inhibit skidding of the rolling elements 500. The spigotbearing biasing member 512 may be spaced apart from the inner race 502of the spigot bearing assembly 410.

Referring to FIG. 5, the spigot bearing biasing member 512 may alsoexert a biasing force on the second rotor bearing assembly 210, whichmay be axially positioned between the first rotor bearing assembly 208and the spigot bearing assembly 410. More specifically, the spigotbearing biasing member 512 may exert a biasing force on the spigotbearing assembly 410, which in turn may exert a biasing force on therotor output flange 290. This biasing force may be transmitted to theouter race 314 of the second rotor bearing assembly 210 via theprotrusion 480 of the rotor output flange 290, which may bias the outerrace 314 toward the first rotor bearing assembly 208.

The spigot bearing biasing member 512 may have any suitableconfiguration. For instance, the spigot bearing biasing member 512 maybe configured as a spring, such as a wave spring or waive washer thatmay extend around the first axis 70. Alternatively, the spigot bearingbiasing member 512 may not extend around the first axis 70. As onenonlimiting example, the spigot bearing biasing member 512 may includeone or more springs, such as coil springs that may be arranged in anaxial direction.

Resolver

Referring to FIGS. 6, 11 and 18, a resolver 600 may be associated withthe electric motor module 24. The resolver 600, which may also bereferred to as a resolver stator, may function as a sensor that mayprovide a signal indicative of rotation of the rotor 206 or therotational position of the rotor 206. For example, the resolver 600 maydetect the position of the rotary disc 466, such as by detecting thepresence or absence of the protrusions of the rotary disc 466 or maydetect rotation of the rotary disc 466. The resolver 600 may be of anysuitable type. For example, the resolver 600 may be an analog resolveror a digital resolver, such as a rotary encoder.

The resolver 600 may generally be configured as a ring that may extendaround the first axis 70. The resolver 600 may also extend around aportion of the rotor output flange 290, and the rotary disc 466 as isbest shown in FIG. 6. The resolver 600 or a portion thereof may bereceived in the rotor output flange hole 434 of the motor cover 214 andmay be mounted to the second side 372 of the motor cover 214. As such,the motor cover 214 may be disposed between the resolver 600 and therotor 206 and the resolver 600 may be accessible from the outside of theelectric motor module 24. Such positioning may also isolate the resolver600 from lubricant in the lubricant chambers of the axle assembly 10 aswill be discussed in more detail below. As is best shown in FIGS. 11 and18, the resolver 600 may include a plurality of elongated slots 602 andan electrical connector 604.

The elongated slots 602 may facilitate mounting of the resolver 600 tothe motor cover 214. A fastener 606, such as a screw or bolt, may extendthrough an associated elongated slot 602 and may secure the resolver 600to the motor cover 214. The elongated slots 602 may be disposed at asubstantially constant radial distance from the first axis 70 and maypermit the resolver 600 to be rotated about the first axis 70 when thefasteners 606 are not fully tightened.

The electrical connector 604 may be disposed proximate the outsideperimeter or outside circumference of the resolver 600. The electricalconnector 604 may extend through the resolver slot 382 in the motorcover 214. The electrical connector 604 may be connected to anelectrical power source to provide power to the resolver 600 and mayfacilitate electronic communication with an axle controller that maycontrol operation of the electric motor module 24.

A resolver cover 608 may extend over the electrical connector 604 toprotect the electrical connector 604 and separate the electricalconnector 604 from the rotor 206. The resolver cover 608 may be fastenedto the first side 370 of the motor cover 214 in any suitable manner,such as with one or more fasteners 610, such as screws.

As is best shown in FIG. 6, the resolver 600 may be axially positionedbetween the motor cover 214 and a seal carrier plate 620. The sealcarrier plate 620 may be spaced apart from the resolver 600. The sealcarrier plate 620, which is also shown in FIGS. 11 and 18, may generallybe configured as a hollow circular disc that may extend around the firstaxis 70. As is best shown in FIG. 6, the seal carrier plate 620 mayextend further toward the first axis 70 and further away from the firstaxis 70 than the resolver 600.

Referring to FIGS. 6, 11 and 18, the seal carrier plate 620 may bemounted to the motor cover 214. In at least one configuration, the sealcarrier plate 620 may include a seal carrier plate hole 630, an outersurface 632, one or more fastener holes 634, and a seal carrier plateflange 636.

The seal carrier plate hole 630 may extend around the first axis 70. Theseal carrier plate hole 630 may receive a portion of the rotor outputflange 290 and an inner seal 640. The inner seal 640 may extend aroundthe rotor output flange 290 and may extend from the seal carrier plate620 to the second seal support surface 454 of the rotor output flange290. As such, the rotor output flange 290 may separate the inner seal640 from the sun gear of the gear reduction module 26.

The outer surface 632 may be disposed opposite the seal carrier platehole 630. As such, the outer surface 632 may face away from the firstaxis 70.

One or more fastener holes 634 may extend through the seal carrier plate620. The fastener holes 634 may be configured as through holes that maybe positioned between the seal carrier plate hole 630 and the outersurface 632. Each fastener hole 634 may receive a fastener 642, such asa screw or bolt, that may secure the seal carrier plate 620 to the motorcover 214.

The seal carrier plate flange 636 may be disposed between the sealcarrier plate hole 630 and the outer surface 632. The seal carrier plateflange 636 may extend toward the motor cover 214. In at least oneconfiguration, the seal carrier plate flange 636 may be configured as aring that may extend continuously around the first axis 70. The sealcarrier plate flange 636 may support an outer seal 644. The outer seal644 may have any suitable configuration. For example, the outer seal 644may be configured as an O-ring. The outer seal 644 may extend around theseal carrier plate flange 636 and may extend from the seal carrier plateflange 636 to the motor cover 214 when the seal carrier plate 620 ismounted on the motor cover 214.

Providing a resolver 600 and a seal carrier plate 620 that areaccessible from the outside of the electric motor module 24 may simplifyassembly as compared to a configuration in which the resolver 600 ispositioned on the opposite side of the motor cover 214. In aconfiguration where the resolver is positioned on the side of the motorcover 214 that faces toward the rotor 206, the resolver would besusceptible to falling into the electric motor module 24 whenunfastened. Moreover, if a curable adhesive or sealant was providedbetween the resolver 600 and the motor cover 214 then the resolver wouldneed to be adjusted to its final rotational position before the adhesiveor sealant cures or solidifies. The configuration described above mayeliminate such adhesives or sealants and may provide easier access tothe resolver 600 and the seal carrier plate 620.

An example of an assembly sequence for the resolver 600 and the sealcarrier plate 620 is as follows.

First, the differential carrier 42 may be provided. The differentialcarrier 42 may be provided with the drive pinion 22 assembled to thedifferential carrier 42 and rotatably supported on the first and seconddrive pinion bearings 150, 170.

Second, the electric motor module 24 may be assembled to thedifferential carrier 42. Assembling the electric motor module 24 to thedifferential carrier 42 may include mounting the rotor 206 on thebearing support wall 64 of the differential carrier 42 and mounting thesubassembly that includes the motor housing 200, the coolant jacket 202,and the stator 204 to the differential carrier 42. The motor cover 214may also be mounted to the motor housing 200 as previously described.The rotor output flange 290 may be mounted on the rotor 206 before themotor cover 214 is mounted to the motor housing 200. Similarly, theresolver 600 and the resolver cover 608 may be mounted to the motorcover 214 before the motor cover 214 is mounted to the motor housing200. The drive pinion 22 and the rotor output flange 290 may extendthrough the motor cover opening 374 and the resolver 600 after the motorcover 214 is installed.

Third, the rotational position of the resolver 600 may be assessed andadjusted if necessary. The rotational position of the resolver 600 withrespect to the first axis 70 may not be precisely aligned with therotational position of the rotor 206 when the motor cover 214 is mountedto the motor housing 200. The rotational position of the resolver 600may be assessed in a manner known by those skilled in the art. Forexample, the rotor 206 may be rotated about the first axis 70, which mayalso rotate the rotor output flange 290 and the rotary disc 466, and therotational position of the rotor 206 and the rotary disc 466 then may besynchronized with the resolver 600. The rotor 206 may be rotatedmanually, such as by turning the rotor output flange 290, orelectrically. The rotational position of the resolver 600 may beadjusted by loosening the fasteners 606 (but not necessarily removingthe fasteners 606 from the motor cover 214) to permit the resolver 600to be rotated about the first axis 70 and with respect to the fasteners606 via the elongated slots 602. Once the resolver 600 is properlyaligned, then the fasteners 606 may be tightened to secure the resolver600 and inhibit rotation of the resolver about the first axis 70.

Fourth, the seal carrier plate 620 may be mounted to the motor cover 214after the resolver 600 is secured. The seal carrier plate 620 may bemounted and secured with the fasteners 642 and may include the innerseal 640 and the outer seal 644.

Gear Reduction Module

Referring to FIG. 2, the gear reduction module 26, if provided, maytransmit torque from the electric motor module 24 to the differentialassembly 30. As such, the gear reduction module 26 may be operativelyconnected to the electric motor module 24 and the differential assembly30. The gear reduction module 26 may be disposed outside of thedifferential carrier 42 and may be primarily disposed outside of theelectric motor module 24, thereby providing a modular construction thatmay be mounted to the electric motor module 24 when gear reduction isdesired. Such a configuration may facilitate standardized configurationsof the differential carrier 42 and/or the electric motor module 24.

The gear reduction module 26 may be disposed adjacent to the motor cover214. In addition, the gear reduction module 26 may be primarily receivedor at least partially received in a shift mechanism housing 900 that maybe mounted to the motor cover 214 as will be discussed in more detailbelow.

The gear reduction module 26 may be provided in various configurations,such as planetary gear set configurations and non-planetary gear setconfigurations. Referring to FIGS. 2, 12 and 19, an example of a gearreduction module 26 that has a planetary gear set 700 is shown. In sucha configuration, the gear reduction module 26 may include a sun gear710, planet gears 712, a planetary ring gear 714, and a planet gearcarrier 716. The planetary gear set 700 will primarily be described inthe context of an axle assembly that may include an electric motormodule 24; however, it is to be understood that the planetary gear set700 described below may be provided with axle assemblies that do nothave an electric motor module. For example, the planetary gear set 700may be configured as an interaxle differential unit or may be used toprovide gear reduction at a wheel end.

Referring to FIGS. 6, 12 and 19, the sun gear 710 may be disposedproximate the center of the planetary gear set 700 and may be rotatableabout the first axis 70. The sun gear 710 may be operatively connectableto the electric motor module 24. In addition, the sun gear 710 mayextend into the motor cover opening 374 of the motor cover 214. As isbest shown primarily with reference to FIGS. 12 and 19, the sun gear 710may be a hollow tubular body that may include a first end surface 720, asecond end surface 722, a sun gear hole 724, a sun gear spline 726, afirst gear portion 728, and a second gear portion 730.

The first end surface 720 may be disposed at an end of the sun gear 710that may face toward the axle housing 40. The first end surface 720 mayextend into the motor cover opening 374.

The second end surface 722 may be disposed at an end of the sun gear 710that may face away from the axle housing 40. As such, the second endsurface 722 may be disposed opposite the first end surface 720. Thesecond end surface 722 may be disposed outside of the motor coveropening 374 and inside the shift mechanism housing 900. A thrust bearing732 may extend from the second end surface 722 to the planet gearcarrier 716 to help inhibit axial movement of the sun gear 710 andfacilitate rotation of the sun gear 710 with respect to the planet gearcarrier 716.

The sun gear hole 724 may extend from the first end surface 720 to thesecond end surface 722. The sun gear hole 724 may extend along and maybe centered about the first axis 70. The drive pinion 22 may extendthrough the sun gear hole 724 and may be spaced apart from the sun gear710.

The sun gear spline 726 may facilitate coupling of the sun gear 710 to arotor output flange 290. In at least one configuration, the sun gearspline 726 may be disposed opposite the sun gear hole 724 and may extendfrom or may be disposed proximate the first end surface 720. As such,the sun gear spline 726 may be received inside the rotor output flange290 and may mesh with the rotor output flange spline 440. It is alsocontemplated that the sun gear spline 726 may be disposed in the sungear hole 724 and the rotor output flange 290 may be received inside thesun gear 710.

The first gear portion 728 may be disposed in the sun gear hole 724. Forexample, the first gear portion 728 may be disposed proximate the secondend surface 722 of the sun gear 710. Teeth of the first gear portion 728may be arranged around the first axis 70 and may extend toward the firstaxis 70 and may be configured to mesh with teeth of a shift collar 904as will be discussed in more detail below.

The second gear portion 730 may be disposed opposite the first gearportion 728. The second gear portion 730 may be disposed proximate thesecond end surface 722 of the sun gear 710. The second gear portion 730may have teeth that may mesh with teeth of the planet gears 712. Theteeth of the second gear portion 730 may be arranged around the firstaxis 70 and may extend away from the first axis 70.

The planet gears 712 may be rotatably disposed between the sun gear 710and the planetary ring gear 714. Each planet gear 712 may have a holeand a set of teeth. The hole may be a through hole that may extendthrough the planet gear 712. The set of teeth may be disposed oppositethe hole. The set of teeth may mesh with teeth of the second gearportion 730 of the sun gear 710 and teeth on the planetary ring gear714. The teeth may have any suitable configuration. In the configurationshown, the teeth are provided with a helical configuration however,other tooth configurations may be provided. Each planet gear 712 may beconfigured to rotate about a different planet gear axis of rotation. Theplanet gear axes of rotation may extend substantially parallel to thefirst axis 70.

Referring to FIG. 25, the planet gears 712 may be grouped into two sets.These sets may be referred to as a first set of planet gears 740 and asecond set of planet gears 750. The first set of planet gears 740 andthe second set of planet gears 750 may have individual planet gears thatmay have the same configuration.

The first set of planet gears 740 may include multiple planet gears thatmesh with the sun gear 710 and the planetary ring gear 714. For example,the first set of planet gears 740 may have n members, where n is aninteger greater than 1. The members of the first set of planet gears 740may have the same configuration, may be spaced apart from each other,and may be arranged around the first axis 70 in a repeatingrelationship. For instance, the members of the first set of planet gears740 may be equidistantly spaced around the first axis 70 with respect toeach other. Each member of the first set of planet gears 740 may bearranged around the first axis 70 at an angle α₁ with respect to eachother. For instance, if n=3, then α₁=120°; if n=4, then α₁ equals 90°,and so on. The axes of rotation of each member of the first set ofplanet gears 740, which may also be referred to as a first planet gearaxis 742, may be positioned at a substantially constant radial distancefrom the first axis 70.

Each member of the first set of planet gears 740 may be arranged orpositioned between two members of the second set of planet gears 750. Inat least one configuration, each member of the first set of planet gears740 may be positioned closer to one member of the second set of planetgears 750 than all other members of the second set of planet gears 750.This may result in the planet gears appearing to be grouped in pairsthat include one member of the first set of planet gears 740 and onemember of the second set of planet gears 750.

Each member of the first set of planet gears 740 may be disposed“in-phase” with each other. As such, each member of the first set ofplanet gears 740 may be provided at a common rotational position orrotational orientation with respect to the planetary ring gear 714.Thus, the members of first set of planet gears 740 may have commonmeshing relationships with the planetary ring gear 714. For example,each member of the first set of planet gears 740 may be positioned suchthat a corresponding tooth of the planetary ring gear 714 is receivedbetween and is centered between two adjacent teeth of the planet gear.Such positioning is represented in FIG. 25 by triangles that extend fromthe planetary ring gear 714 toward the first axis 70. A magnifiedillustration of such positioning is shown in FIG. 26 in which theplanetary ring gear tooth that is received between and centered betweenadjacent teeth of a member of the first set of planet gears 740. In atleast one configuration, the planetary ring gear tooth that is receivedbetween and centered between adjacent teeth of a member of the first setof planet gears 740 may positioned along a radial line L1 that mayextend through the first axis 70 and through a corresponding firstplanet gear axis 742 about which a member of the first set of planetgears 740 may rotate. The planetary ring gear tooth or a cross sectionof the planetary ring gear tooth may be centered about the radial lineL1. In-phase positioning along with equidistant spacing of the membersof the first set of planet gears 740 may help cancel radial vibrationexcitations.

The second set of planet gears 750 may also include multiple planetgears that mesh with the sun gear 710 and the planetary ring gear 714.For example, the second set of planet gears 750 may have n members,where n is an integer greater than 1. The members of second set ofplanet gears 750 may have the same configuration, may be spaced apartfrom each other, and may be arranged around the first axis 70 in arepeating relationship. For instance, the second set of planet gears 750may be equidistantly spaced around the first axis 70 with respect toeach other. Each member of the second set of planet gears 750 may bearranged around the first axis 70 at an angle α₂ with respect to eachother. Angle α_(l) may equal angle α₂. The axes of rotation of eachmember of the second set of planet gears 750 which may also be referredto as a second planet gear axis 752, may be positioned at asubstantially constant radial distance from the first axis 70. Inaddition, each member of the second set of planet gears 750 may bearranged or positioned between two members of the first set of planetgears 740. In at least one configuration, each member of the first setof planet gears 740 may be positioned closer to one member of the secondset of planet gears 750 than all other members of the second set ofplanet gears 750. Members of the first set of planet gears 740 andmembers of the second set of planet gears 750 may not mesh with eachother.

Each member of the second set of planet gears 750 may be disposed“in-phase” with each other and may be positioned in counterphase withrespect to the first set of planet gears 740. For instance, each memberof the second set of planet gears 750 may be provided at a commonrotational position or rotational orientation with respect to theplanetary ring gear 714. Thus, the members of second set of planet gears750 may have common meshing relationships with the planetary ring gear714. However, the members of the second set of planet gears 750 may nothave common meshing relationships with the first set of planet gears740. For example, each member of the second set of planet gears 750 maybe positioned such that a tooth of each member of the second set ofplanet gears 750 is received between and is centered between twoadjacent teeth of the planetary ring gear 714 when a planetary ring geartooth is received between and is centered between two adjacent teeth ofeach member of the first set of planet gears 740. Such positioning isrepresented in FIG. 25 by triangles that extend from the members of thesecond set of planet gears 750 away from the first axis 70. A magnifiedillustration of such positioning is shown in FIG. 26 in which the planetgear tooth of the member of the second set of planet gears 750 that isreceived between and centered between adjacent teeth of the planetaryring gear 714 is positioned along a radial line L2 that may extendthrough the first axis 70 and through a corresponding second planet gearaxis 752 about which a member of the second set of planet gears 750 mayrotate. Counterphase positioning of the second set of planet gears 750with respect to the first set of planet gears 740 may help cancelrotational vibration excitations. As a result, radial and rotationalvibration excitations or torque ripples in the planetary gear set 700may be substantially or fully cancelled. Moreover, the unequaldistribution or angular positioning of the first set of planet gears 740with respect to the second set of planet gears 750 may facilitateproviding a stiffer planet gear carrier 716.

Referring to FIGS. 6, 12 and 19, the planetary ring gear 714 may extendaround the first axis 70 and may receive the planet gears 712. Theplanetary ring gear 714 may include a set of planetary ring gear teeththat may extend toward the first axis 70 and may mesh with teeth on theplanet gears 712. The planetary ring gear 714 may be stationary withrespect to the first axis 70. For example, the planetary ring gear 714may be received in and may be fixedly disposed on the shift mechanismhousing 900. In at least one configuration, a plurality of pins 760 maybe partially received in grooves located along the outside circumferenceof the planetary ring gear 714 and may be partially received incorresponding grooves in the shift mechanism housing 900 to inhibitrotation of the planetary ring gear 714.

The planet gear carrier 716 may be rotatable about the first axis 70 andmay rotatably support the planet gears 712. In at least oneconfiguration, the planet gear carrier 716 may include a planet gearcarrier hole 770, a planet gear carrier ring 772, a planet gear carriergear portion 774, a first planet gear carrier flange 776, and a secondplanet gear carrier flange 778.

The planet gear carrier hole 770 may be a through hole that may extendthrough planet gear carrier 716. The planet gear carrier hole 770 mayextend along and may be centered about the first axis 70.

The planet gear carrier ring 772 may at least partially define theplanet gear carrier hole 770. The planet gear carrier ring 772 mayextend around the first axis 70 and may extend in an axial directionaway from the second flange. The planet gear carrier ring 772 may beconfigured to support a support bearing 780 and a tone ring 782. Forexample, the planet gear carrier ring 772 may include a bearing mountingsurface 784 and a tone ring mounting surface 786.

The bearing mounting surface 784 may face away from the first axis 70and may extend around the first axis 70. The bearing mounting surface784 may be axially positioned between the second planet gear carrierflange 778 and a distal end of the planet gear carrier ring 772. Aninner race of the support bearing 780 may receive and may be disposed onthe bearing mounting surface 784. The support bearing 780 may rotatablysupport the planet gear carrier 716 on the shift mechanism housing. Afastener 790, such as a snap ring, may be received in a groove in theplanet gear carrier ring 772 to inhibit axial movement of the supportbearing 780.

The tone ring mounting surface 786 may also face away from the firstaxis 70 and may extend around the first axis 70. The tone ring mountingsurface 786 may extend from the distal end of the planet gear carrierring 772 or may be disposed between the distal end of the planet gearcarrier ring 772 in the bearing mounting surface 784. The tone ring 782may have a plurality of teeth and may receive and may be disposed on thetone ring mounting surface 786.

The planet gear carrier gear portion 774 may be disposed in the planetgear carrier ring 772 and may extend into the planet gear carrier hole770. Teeth of the planet gear carrier gear portion 774 may be arrangedaround the first axis 70 and may extend toward the first axis 70.

The first planet gear carrier flange 776, which may also be referred toas a first flange, may be disposed opposite the planet gear carrier ring772. The first planet gear carrier flange 776 may extend away from thefirst axis 70. The first planet gear carrier flange 776 may include aplurality of openings 800 and a set of fastener holes 802.

The openings 800 may facilitate mounting of the planet gears 712 as willbe discussed in more detail below. The openings 800 may be configured asthrough holes.

Referring to FIGS. 6 and 19, a fastener hole 802 may extend to theopening 800. In at least one configuration, the fastener holes 802 mayextend along radial lines with respect to the first axis 70.

Referring to FIGS. 6, 12 and 19, the second planet gear carrier flange778, which may also be referred to as a second flange, may be spacedapart from the first planet gear carrier flange 776. The second planetgear carrier flange 778 may be axially positioned between the firstplanet gear carrier flange 776 and the planet gear carrier ring 772. Thesecond planet gear carrier flange 778 may extend away from the firstaxis 70 and may have a similar configuration as the first planet gearcarrier flange 776. The second planet gear carrier flange 778 mayinclude a plurality of openings 810 and a set of lubricant holes 812.

The openings 810 in the second planet gear carrier flange 778 may bealigned with a corresponding opening 800 in the first planet gearcarrier flange 776. The openings 800, 810 may facilitate mounting of theplanet gears 712 between the first planet gear carrier flange 776 andthe second planet gear carrier flange 778.

A lubricant hole 812 may extend through the second planet gear carrierflange 778 to each opening 800. In at least one configuration, thelubricant holes 812 may extend along radial lines with respect to thefirst axis 70. It is also contemplated that the positioning of some orall of the lubricant holes 812 and the fastener holes 802 may beinterchanged between the first planet gear carrier flange 776 and thesecond planet gear carrier flange 778.

Various components may facilitate mounting of a planet gear 712. Thesecomponents may include one or more planet pins 820 and one or more of afirst roller bearing assembly 822, a second roller bearing assembly 824,a spacer 826, a first washer 828, a second washer 830, and a securingpin 832.

A planet pin 820 may rotatably support each planet gear 712. The planetpin 820 may extend from the first planet gear carrier flange 776 to thesecond planet gear carrier flange 778. For example, a planet pin 820 mayextend into or through the hole in a corresponding planet gear 712 andinto or through an opening 800 in the first planet gear carrier flange776 and an opening 810 in the second planet gear carrier flange 778. Assuch, the planet pins 820 may not be cantilevered from the planet gearcarrier 716. Moreover, the planet pins 820 may be substantially rigidand may not deflect with respect to a corresponding planet gear axis,such as a first planet gear axis 742 or a second planet gear axis 752.In addition, each planet pin 820 may have a securing pin hole 840, anaxial bore 842, a first connection passage 844, and a second connectionpassage 846 as is best shown in FIG. 6.

The securing pin hole 840 may partially or completely through the planetpin 820. A securing pin 832 may be received in the securing pin hole 840and may be received in a fastener hole 802 of the first planet gearcarrier flange 776 to help inhibit axial movement of a planet pin 820with respect to the planet gear carrier 716. The securing pins 832 mayhave any suitable configuration.

The axial bore 842 may extend in an axial direction from an end of theplanet pin 820. The axial bore 842 may be a blind hole in one or moreembodiments. A plug 852 may be received in an end of the axial bore 842to help direct lubricant flow as will be discussed in more detail below.The plugs 852 may have any suitable configuration. For instance, theplugs 852 may be configured as set screws.

The first connection passage 844 may extend from the axial bore 842 tothe spacer 826. As such, the first connection passage 844 may bedisposed near the center of a planet pin 820.

The second connection passage 846 may be spaced apart from the firstconnection passage 844. The second connection passage 846 and may extendfrom the axial bore 842 to a lubricant hole 812 in the second planetgear carrier flange 778. The second connection passage 846 may bedisposed adjacent to a plug 852.

Referring to FIGS. 6, 12 and 19, the first roller bearing assembly 822and the second roller bearing assembly 824 may receive a planet pin 820and may be received inside a corresponding planet gear 712. The firstroller bearing assembly 822 and the second roller bearing assembly 824may rotatably support the planet gear 712.

The spacer 826 may receive a planet pin 820 and may be axiallypositioned between the first roller bearing assembly 822 and the secondroller bearing assembly 824. The spacer 826 may have a larger insidediameter than the outside diameter of the planet pin 820 to allowlubricant to flow inside the spacer 826 to help lubricate the firstroller bearing assembly 822 and the second roller bearing assembly 824.

The first washer 828 and the second washer 830 may receive a planet pin820. The first washer 828 may extend from the first planet gear carrierflange 776 to the first roller bearing assembly 822. The second washer830 may extend from the second planet gear carrier flange 778 to thesecond roller bearing assembly 824. As such, the first washer 828 andthe second washer 830 may cooperate to inhibit axial movement of theplanet gear 712, the first roller bearing assembly 822, the secondroller bearing assembly 824, or combinations thereof.

Shift Mechanism

Referring to FIG. 2, the shift mechanism 28 may be disposed at an end ofthe axle assembly 10 that may be disposed opposite the axle housing 40.The shift mechanism 28 may be disposed on the motor cover 214.

The gear reduction module 26 may cooperate with the shift mechanism 28to provide a desired gear reduction ratio to change the torque providedfrom the electric motor module 24 to the differential assembly 30, andhence to the axle shafts 32 of the axle assembly 10. For example, thegear reduction module 26 may provide a first drive gear ratio and asecond drive gear ratio. The first drive gear ratio, which may bereferred to as a low range gear ratio, may provide gear reduction fromthe electric motor module 24 to the differential assembly 30 and henceto the axle shafts 32. As a nonlimiting example, the first drive gearratio may provide a 2:1 gear ratio or more. The first drive gear ratiomay provide increased torque to a vehicle traction wheel as compared tothe second drive gear ratio.

The second drive gear ratio, which may be referred to as a high rangegear ratio, may provide a different gear reduction ratio or lesser gearreduction ratio than the first drive gear ratio. For instance, thesecond drive gear ratio may provide a 1:1 gear ratio. The second drivegear ratio may facilitate faster vehicle cruising or a cruising gearratio that may help improve fuel economy.

In addition, a neutral position or neutral drive gear ratio may beprovided in which torque may not be provided to the differentialassembly 30 by the electric motor module 24. As such, torque may not betransmitted between the gear reduction module 26 and the drive pinion 22when a shift collar is in the neutral position.

Referring to FIGS. 2, 13 and 20, the shift mechanism 28 may include ashift mechanism housing 900, an end plate 902, a shift collar 904, andan actuator 906.

The shift mechanism housing 900 may be disposed on the motor cover 214and may be mounted to a side of the motor cover 214 that may be disposedopposite the differential carrier 42. For example, the shift mechanismhousing 900 may be mounted to the motor cover 214 with one or morefasteners 910, such as bolts. The shift mechanism housing 900 may atleast partially receive the gear reduction module 26. In addition, theshift mechanism housing 900 may facilitate mounting of the actuator 906and may at least partially receive the shift collar 904. As is bestshown in FIG. 6, the shift mechanism housing 900 may rotatably supportthe planet gear carrier 716 via the support bearing 780. A retainer 908may be mounted to the shift mechanism housing 900 to inhibit axialmovement of the support bearing 780. In at least one configuration, theretainer 908 may engage an outer race of the support bearing 780 toinhibit axial movement toward the motor cover 214.

The end plate 902, which may also be referred to as an end cap, may bedisposed on an end of the shift mechanism housing 900 that may bedisposed opposite the axle housing 40. For example, the end plate 902may be mounted to the shift mechanism housing 900 with a plurality offasteners 920, such as bolts. The end plate 902 may help support theactuator 906. For example, the end plate 902 may have a support feature922 that may support a shaft 930 that may support and facilitate axialmovement of a shift fork 932 as will be discussed in more detail below.The shaft 930 may also be supported by the shift mechanism housing 900.

The shift collar 904 may be at least partially received in the shiftmechanism housing 900. For instance, the shift collar 904 may be atleast partially received in the shift mechanism housing 900 and mayextend through components of the gear reduction module 26, such as theplanet gear carrier 716. In at least one configuration such as is bestshown in FIGS. 13 and 20, the shift collar 904 may include a shiftcollar hole 940, a shift collar spline 942, a shift collar groove 944,and a shift collar gear 946.

The shift collar hole 940 may extend through the shift collar 904 andmay extend around the first axis 70. The shift collar hole 940 mayreceive the shaft portion 122 of the drive pinion 22.

Referring to FIG. 20, the shift collar spline 942 may be disposed in theshift collar hole 940 and may be axially positioned near a first end ofthe shift collar 904 that may face toward the differential carrier 42.The shift collar spline 942 may extend toward the first axis 70 and maymate with the spline 140 of the drive pinion 22. The mating splines mayallow the shift collar 904 to move in an axial direction or along thefirst axis 70 while inhibiting rotation of the shift collar 904 aboutthe first axis 70 with respect to the drive pinion 22. Thus, the shiftcollar 904 may be rotatable about the first axis 70 with the drivepinion 22.

The shift collar groove 944 may be disposed proximate a second end ofthe shift collar 904 that may face toward the end plate 902. The shiftcollar groove 944 may face away from the first axis 70 and may extendaround the first axis 70. The shift collar groove 944 may receive theshift fork 932, which may operatively connect the shift collar 904 tothe actuator 906.

The shift collar gear 946 may be disposed between the first end and thesecond end of the shift collar 904. The shift collar gear 946 may haveteeth that may be arranged around the first axis 70 and that may extendaway from the first axis 70. An annular groove 950 that may extendaround the first axis 70 may be provided in the shift collar gear 946.The annular groove 950 may receive a stop 952 that may limit axialmovement of the shift collar 904. The stop 952 may have any suitableconfiguration. For instance, the stop 952 may include one or more snaprings.

The shift collar 904 may be movably disposed on the drive pinion 22. Theshift collar 904 may selectively engage a gear ratio. More specifically,the shift collar 904 may move axially or in a direction that extendsalong the first axis 70 between a first position, a second position, anda third position. These positions are illustrated in FIGS. 2-4.

Referring to FIG. 2 as well as the magnified portion of FIG. 2 shown inFIG. 6, the shift collar 904 is shown in the first position. In thefirst position, the shift collar 904 may couple the planet gear carrier716 to the drive pinion 22. For example, the teeth of the shift collargear 946 may mesh with the teeth of the planet gear carrier gear portion774 of the planet gear carrier 716. As such, torque that is provided bythe electric motor module 24 may be transmitted through the rotor outputflange 290, sun gear 710, planet gears 712, and planet gear carrier 716to the shift collar 904 and from the shift collar 904 to the drivepinion 22.

Referring to FIG. 3, the shift collar 904 is shown in a second positionor neutral position. The second position may be axially positionedbetween the first position and the third position. In the secondposition, the shift collar 904 may not couple the gear reduction module26 to the drive pinion 22. For example, the teeth of the shift collargear 946 may not mesh with the teeth of the sun gear 710 or the planetgear carrier 716. As such, torque that is provided by the electric motormodule 24 may not be transmitted to the shift collar 904 or the drivepinion 22. The shift collar 904 may be disposed closer to the axlehousing 40 when in the second position than when in the first position.

Referring to FIG. 4, the shift collar 904 is shown in the thirdposition. In the first position, the shift collar 904 may couple the sungear 710 to the drive pinion 22. For example, the teeth of the shiftcollar gear 946 may mesh with the teeth of the second gear portion 730of the sun gear 710. As such, torque that is provided by the electricmotor module 24 may be transmitted through the rotor output flange 290and sun gear 710 to the shift collar 904 and from shift collar 904 tothe drive pinion 22. The shift collar 904 may be disposed closer to theaxle housing 40 when in the third position than when in the secondposition.

It is also contemplated that the shift collar may be omitted such thatthe gear reduction module may provide a single gear ratio rather thanmultiple gear ratios. For example, the planet gear carrier 716 may becoupled to the drive pinion 22 to provide a low range gear ratio withouta high range gear ratio.

The actuator 906 may be disposed on the shift mechanism housing 900. Theactuator 906 may move the shift collar 904 along the first axis 70between the first, second, and third positions. For example, theactuator 906 may have an output shaft that may be rotatable about anaxis. A cam 960 may be mounted to the output shaft and may rotate withthe output shaft. The cam 960 may operatively connect the actuator 906to the shift fork 932. As such, rotation of the output shaft may actuatethe shift fork 932 along the shaft 930, which in turn may move the shiftcollar 904 along the first axis 70. The actuator 906 may be of anysuitable type. For example, the actuator 906 may be an electrical,electromechanical, pneumatic or hydraulic actuator.

Lubricant Chambers

Referring to FIG. 4, the axle assembly 10 may be divided into three mainchambers. These chambers may include a first lubricant chamber 1000, asecond lubricant chamber 1002, and an air chamber 1004.

The first lubricant chamber 1000 may be primarily defined by the axlehousing 40 and the differential carrier 42. More specifically, the firstlubricant chamber 1000 may be disposed between the axle housing 40 andthe differential carrier 42 and may be disposed inside a majority of thebearing support wall 64. As such, the first lubricant chamber 1000 mayreceive the differential assembly 30, the gear portion 120 of the drivepinion 22, part of the shaft portion 122 of the drive pinion 22, thefirst drive pinion bearing 150, and the second drive pinion bearing 170.In addition, the first lubricant chamber 1000 may receive a firstlubricant 1006. The first lubricant 1006 may be a high shear oil, suchas 75W90 gear oil.

The second lubricant chamber 1002 may be primarily defined by the motorcover 214, rotor output flange 290, the shift mechanism housing 900, andthe end plate 902. More specifically, the second lubricant chamber 1002may be disposed inside a majority of the rotor output flange 290, motorcover 214, and the shift mechanism housing 900. As such, the secondlubricant chamber 1002 may receive the preload nut 190, part of theshaft portion 122 of the drive pinion 22, the planetary gear set 700,and the shift collar 904. The second lubricant chamber 1002 may receivea second lubricant 1008. The second lubricant 1008 may be a differenttype or grade of lubricant than the first lubricant 1006. For example,the second lubricant 1008 may be Emgard® MTF7000 40W gear oil, which mayprovide lower frictional loss properties and cost benefits.

The air chamber 1004 may be primarily defined by the electric motormodule 24 and the differential carrier 42. For example, the bearingsupport wall 64 may cooperate with the motor housing 200 and the motorcover 214 to at least partially define the air chamber 1004. As such,the air chamber 1004 may be primarily disposed in a radial directionbetween the bearing support wall 64 and the motor housing 200 and may beprimarily disposed between the differential carrier 42 and the motorcover 214 in an axial direction. The air chamber 1004 may receivecomponents such as the coolant jacket 202, the stator 204, the rotor206, the first rotor bearing assembly 208, the second rotor bearingassembly 210, rotor bearing preload module 212, the spigot bearingassembly 410, the rotary disc 466, and the resolver 600. A vent may beprovided in the axle assembly 10 to permit the air chamber 1004 tofluidly communicate with the surrounding environment.

The first lubricant chamber 1000, the second lubricant chamber 1002, andthe air chamber 1004 may be separated by various sealing components andmay not be fluidly connected to each other. Such sealing components mayinclude the seal support ring 180 and the inner seal 640 as previouslydiscussed. In addition, sealing components may include a seal mountingring 1010, a first seal 1012, a second seal 1014, and a third seal 1016,which are best shown with reference to FIGS. 5,9 and 16.

The seal mounting ring 1010 may be positioned between the drive pinion22 and the bearing support wall 64. As such, the seal mounting ring 1010may be disposed in the hole 90 that may be defined by the bearingsupport wall 64. In addition, the seal mounting ring 1010 may be fixedlypositioned with respect to the bearing support wall 64. For example, theseal mounting ring 1010 may be received in the hole 90 with aninterference fit. The seal mounting ring 1010 may extend around and maybe spaced apart from the seal support ring 180 and the first sealsupport surface 444 of the rotor output flange 290. In at least oneconfiguration, the seal mounting ring 1010 may include a first side1020, a second side 1022, an outer face 1024, and an inner face 1026.

The first side 1020 may face toward the second drive pinion bearing 170.The first side 1020 may be spaced apart from the second drive pinionbearing 170 in one or more embodiments.

The second side 1022 may be disposed opposite the first side 1020. Assuch, the second side 1022 may face toward the flange portion 432 of therotor output flange 290.

The outer face 1024 may face away from the first axis 70. The outer face1024 may extend from the first side 1020 to the second side 1022 and mayengage the bearing support wall 64.

The inner face 1026 may be disposed opposite the outer face 1024. Assuch, the inner face 1026 may face toward the first axis 70. In at leastone configuration, the inner face 1026 may have a stepped configurationthat may include a first seal mounting surface 1030, a second sealmounting surface 1032, a third seal mounting surface 1034, and anintermediate surface 1036.

The first seal mounting surface 1030 may face toward and may extendaround the seal support ring 180.

The second seal mounting surface 1032 may also face toward and mayextend around the seal support ring 180 and may extend around the firstaxis 70. The second seal mounting surface 1032 may have a differentdiameter than the first seal mounting surface 1030. In the configurationshown, the second seal mounting surface 1032 may have a smaller diameterthan the first seal mounting surface 1030.

The third seal mounting surface 1034 may face toward and may extendaround the first seal support surface 444 of the rotor output flange290. The third seal mounting surface 1034 may have a different diameterthan the first seal mounting surface 1030. In the configuration shown,the third seal mounting surface 1034 may have a smaller diameter thanthe first seal mounting surface 1030.

The intermediate surface 1036 may be axially positioned between thesecond seal mounting surface 1032 and the third seal mounting surface1034. The intermediate surface 1036 or a portion thereof may have asmaller diameter than the second seal mounting surface 1032, the thirdseal mounting surface 1034, or both. Such a configuration may helpinhibit axial movement of seals that may be associated with the secondseal mounting surface 1032 in the third seal mounting surface 1034.

The first seal 1012 may extend between the bearing support wall 64 andthe drive pinion 22. For example, the first seal 1012 may extend fromthe first seal mounting surface 1030 to the seal support ring 180. Thefirst seal 1012 may extend around the seal support ring 180 and may helpseparate the first lubricant chamber 1000 from the second lubricantchamber 1002.

The second seal 1014 may extend between the bearing support wall 64 andthe rotor output flange 290. For example, the second seal 1014 mayextend from the second seal mounting surface 1032 to the first sealsupport surface 444 of the rotor output flange 290. The second seal 1014may extend around the rotor output flange 290 and may help separate theair chamber 1004 from the second lubricant chamber 1002.

The third seal 1016 may be axially positioned between the first seal1012 and the second seal 1014. The third seal 1016 may extend betweenthe bearing support wall 64 and the drive pinion 22. For example, thethird seal 1016 may extend from the third seal mounting surface 1034 tothe seal support ring 180. The third seal 1016 may extend around theseal support ring 180 and may help separate the first lubricant chamber1000 from the second lubricant chamber 1002. The third seal 1016 may bespaced apart from the first seal 1012 such that a cavity 1040 may bedisposed between the first seal 1012 and the third seal 1016. The cavity1040 may be fluidly connected to the air chamber 1004. For instance, thecavity 1040 may be fluidly connected to the air chamber 1004 by at leastone vent passage 1042 that may extend through the seal mounting ring1010. For example, the vent passage 1042 may extend from the inner face1026 of the seal mounting ring 1010 to the second side 1022 of the sealmounting ring 1010. As such, a portion of the vent passage 1042 mayextend from the second side 1022 toward the first side 1020 but not tothe first side 1020. In the configuration shown in FIG. 9, four ventpassages 1042 shown that may be arranged at 90° intervals from eachother; however, it is contemplated that a greater or lesser number ofvent passages may be provided.

Referring to FIG. 6, the inner seal 640 may extend between the sealcarrier plate 620 and the rotor output flange 290. For example, theinner seal 640 may be received in the seal carrier plate hole 630 andmay extend from the seal carrier plate 620 to the second seal supportsurface 454 of the rotor output flange 290. The inner seal 640 mayextend around the rotor output flange 290 and may help separate thesecond lubricant chamber 1002 from the air chamber 1004. The inner seal640 may be spaced apart from the seal mounting ring 1010. As such,various components such as the spigot bearing assembly 410, the rotarydisc 466, and the resolver 600 may be axially positioned between thesecond seal 1014 and the inner seal 640.

Control

Referring to FIG. 23, a schematic representation of an axle system 1100is shown. The axle system 1100 may include the axle assembly 10 as wellas a control system 1102.

The control system 1102 may include multiple electronic controllers. Forexample, the control system 1102 may include an axle controller 1110 anda brake controller 1112. Other electronic controllers may also beprovided but are not depicted. One or more controllers may communicateover a Controller Area Network (CAN) bus of a vehicle. Information thatis communicated over the CAN bus or through multiple controllers mayhave latency issues and may be slower than direct communication.

The axle controller 1110 may control operation of the axle assembly 10.The axle controller 1110 may receive signals from various sensors, suchas the resolver 600, a first speed sensor 1120, and a second speedsensor 1122. In addition, the axle controller 1110 may control theactuator 906 and thereby controls movement of the shift collar 904.

The first speed sensor 1120 may provide a first signal that may beindicative of a rotational speed of a wheel 14. The first speed sensor1120 may be located downstream from the gear reduction module 26. In atleast one configuration, the first speed sensor 1120 may be disposedbetween the differential assembly 30 and a wheel 14. In such aconfiguration, the first speed sensor 1120 may detect rotation of awheel 14, wheel hub 16, or axle shaft 32. For instance, a tone ring 1130that may have a plurality of teeth may be disposed on the wheel hub 16and may rotate with the wheel hub 16 about the wheel axis 18. The firstspeed sensor 1120 may be disposed near the wheel 14 and may detectrotation of the tone ring 1130. A first speed sensor 1120 may beassociated with each wheel 14, wheel hub 16, or axle shaft 32. Thus, twofirst speed sensors 1120 are shown in FIG. 23. It is also contemplatedthat the first speed sensor 1120 may be provided in other locations. Forexample, the first speed sensor 1120 may detect rotation of the drivepinion 22.

The first speed sensor 1120 may be directly electrically connected ordirectly hardwired to the axle controller 1110. For example, a firstconductor 1140 such as a wire may extend from the first speed sensor1120 to the axle controller 1110. Accordingly, the first signal from thefirst speed sensor 1120 may be provided directly from the first speedsensor 1120 to the axle controller 1110 and may not be indirectly routedto the axle controller 1110 via another controller, such as the brakecontroller 1112. As such, the axle controller 1110 may receive the firstsignal faster than if the first signal was indirectly provided and theaxle controller 1110 so that the axle controller 1110 may better controlshifting of the shift collar 904.

The second speed sensor 1122 may provide a second signal that may beindicative of a rotational speed of the gear reduction module 26. Thesecond speed sensor 1122 may be located upstream from the shift collar904. In at least one configuration, the second speed sensor 1122 may bedisposed between the electric motor module 24 and the shift collar 904.In such a configuration, the second speed sensor 1122 may detectrotation of a component of the planetary gear set 700, such as theplanet gear carrier 716. For instance, the second speed sensor 1122 maybe mounted to the shift mechanism housing 900 or extend through a holein the shift mechanism housing 900 as is best shown in FIG. 24 and maydetect rotation of the tone ring 782 that may be disposed on the planetgear carrier 716. It is also contemplated that the second speed sensor1122 may be provided in other locations. For example, the second speedsensor 1122 may detect rotation of the sun gear 710.

The second speed sensor 1122 may be directly electrically connected ordirectly hardwired to the axle controller 1110. For example, a secondconductor 1142 such as a wire may extend from the second speed sensor1122 to the axle controller 1110. Accordingly, the second signal fromthe second speed sensor 1122 may be provided directly from the secondspeed sensor 1122 to the axle controller 1110 and may not be indirectlyrouted to the axle controller 1110 via another controller, such as thebrake controller 1112. As such, the axle controller 1110 may receive thesecond signal faster than if the second signal was indirectly providedand the axle controller 1110 so that the axle controller 1110 may bettercontrol shifting of the shift collar 904.

A third speed sensor 1150 may be provided with the axle system 1100. Thethird speed sensor 1150 may function like the first speed sensor 1120and may detect rotation of the tone ring 1130. The third speed sensor1150 may provide a third signal that may be used by other controllers ofthe control system 1102. For instance, the third signal may be providedto the brake controller 1112 to facilitate control of an antilock brakesystem. The third signal may not be provided to the axle controller 1110to control shifting of the shift collar 904 due to potential latencyissues.

The axle controller 1110 may use the first signal and the second signalto determine when a shift of the shift collar 904 may be executed. Forinstance, the axle controller 1110 may use the first signal and thesecond signal to determine when the rotational speed of the shift collar904 is sufficiently close to the rotational speed of a component of theplanetary gear set 700, such as the sun gear 710 and/or the planet gearcarrier 716 to permit the shift collar 904 to be shifted to or from theneutral position. The axle controller 1110 operate the actuator 906 tomove the shift collar 904 to a desired position when shifting of theshift collar 904 may be executed and completed.

As an example that starts with the shift collar 904 and the firstposition or the third position, the axle controller 1110 may determinewhen the first and second signals are indicative of sufficiently closerotational speeds. The axle controller 1110 may then temporarily relieveor reduced torque on the shift collar 904 by controlling the rotationalspeed of the rotor 206 or reducing power provided from an electricalpower source/inverter 1160 to permit the shift collar 904 to be moreeasily be actuated from the first position or the third position to thesecond (neutral) position. The axle controller 1110 may then operate theactuator 906 to move the shift collar 904 to the second position.

The axle controller 1110 may move the shift collar 904 from the secondposition to either the first position or the third position bycontrolling the rotational speed of the rotor 206 to synchronize therotational speed of the shift collar 904 with the sun gear 710 to allowthe shift collar 904 to move to the second position to the firstposition or may synchronize the rotational speed of the shift collar 904with the planet gear carrier 716 to allow the shift collar 904 to movefrom the neutral position to the third position

Differential Assembly and Axle Shafts

Referring to FIG. 2, the differential assembly 30 may be at leastpartially received in the center portion 50 of the housing assembly 20.The differential assembly 30 may transmit torque to the wheels 14 andpermit the wheels 14 to rotate at different velocities. The differentialassembly 30 may be operatively connected to the axle shafts 32 and maypermit the axle shafts 32 to rotate at different rotational speeds in amanner known by those skilled in the art. As such, the differentialassembly 30 may receive torque via the ring gear 110 and provide torqueto the axle shafts 32.

Referring to FIGS. 1, 2 and 23, the axle shafts 32 may transmit torquefrom the differential assembly 30 to corresponding wheel hubs 16 andwheels 14. For example, two axle shafts 32 may be provided such thateach axle shaft 32 extends through a different arm portion 52 of axlehousing 40. The axle shafts 32 may extend along and may be rotated aboutthe wheel axis 18 by the differential assembly 30. Each axle shaft 32may have a first end and a second end. The first end may be operativelyconnected to the differential assembly 30. The second end may bedisposed opposite the first end and may be operatively connected to awheel 14. Optionally, gear reduction may be provided between an axleshaft 32 and a wheel 14.

While exemplary embodiments are described above, it is not intended thatthese embodiments describe all possible forms of the invention. Rather,the words used in the specification are words of description rather thanlimitation, and it is understood that various changes may be madewithout departing from the spirit and scope of the invention.Additionally, the features of various implementing embodiments may becombined to form further embodiments of the invention.

What is claimed is:
 1. An axle assembly comprising: a differentialcarrier; an electric motor module mounted to the differential carrier,the electric motor module including a motor housing, a stator that isfixedly disposed in the motor housing, a rotor that is received in thestator and is rotatable about an axis, and a motor cover that is mountedto the motor housing opposite the differential carrier and is spacedapart from the differential carrier; a rotor output flange that isfixedly mounted to the rotor and that extends into a motor cover openingin the motor cover; a resolver that is mounted to a side of the motorcover that faces away from the rotor; and a seal carrier plate that ismounted to the motor cover and is completely received inside the motorcover, wherein the resolver is axially positioned between the sealcarrier plate and the motor cover and the seal carrier plate is spacedapart from the resolver.
 2. The axle assembly of claim 1 wherein theseal carrier plate extends further toward the axis than the resolver. 3.The axle assembly of claim 1 wherein the seal carrier plate has a sealcarrier plate flange that is disposed between a seal carrier plate holeand an outer surface of the seal carrier plate that is disposed oppositethe seal carrier plate hole, and an outer seal extends from the sealcarrier plate flange to the motor cover.
 4. The axle assembly of claim 1wherein an inner seal is received in a seal carrier plate hole andextends from the seal carrier plate to the rotor output flange.
 5. Theaxle assembly of claim 4 wherein a sun gear of a planetary gear set isreceived inside the rotor output flange and the inner seal is spacedapart from the sun gear.
 6. An axle assembly comprising: a differentialcarrier; an electric motor module mounted to the differential carrier,the electric motor module including a motor housing, a stator that isfixedly disposed in the motor housing, a rotor that is received in thestator and is rotatable about an axis, and a motor cover that is mountedto the motor housing opposite the differential carrier, the motor coverdefining a motor cover opening; a rotor output flange that is fixedlymounted to the rotor, the rotor output flange including a tubular bodythat extends around the axis and that is received inside the motor coveropening; the tubular body including: a spigot bearing support surfacethat extend around the axis and supports a spigot bearing that rotatablysupports the rotor output flange on the motor cover; a first outergroove that receives a fastener that inhibits axial movement of thespigot bearing; a rotary disc support surface that extends around theaxis and is offset from the spigot bearing support surface, the rotarydisc support surface supporting a rotary disc: a second outer groovethat receives a second fastener that inhibits axial movement of therotary disc; and a second seal support surface that extends around theaxis, is offset from the rotary disc support surface, and extends from adistal end of the tubular body toward the second outer groove, thesecond seal support surface supporting an inner seal; and a resolverthat is mounted to a side of the motor cover that faces away from therotor.
 7. The axle assembly of claim 6 wherein the rotor output flangeis mounted to the rotor before the motor cover is mounted to the motorhousing.
 8. The axle assembly of claim 6 wherein the second seal supportsurface is disposed closer to the axis than the rotary disc supportsurface.
 9. The axle assembly of claim 8 wherein the rotary disc supportsurface is disposed closer to the axis than the spigot bearing supportsurface.
 10. The axle assembly of claim 9 wherein the resolver isaxially positioned between a seal carrier plate and the motor cover. 11.The axle assembly of claim 10 wherein the rotor output flange extendsthrough the resolver and the seal carrier plate.
 12. The axle assemblyof claim 11 wherein the seal carrier plate has a seal carrier plateflange extends toward the motor cover and wherein an outer seal extendsaround the seal carrier plate flange and engages the motor cover. 13.The axle assembly of claim 12 wherein the inner seal is received in aseal carrier plate hole and extends from the seal carrier plate to therotor output flange.
 14. The axle assembly of claim 11, wherein theresolver detects a position of the rotary disc.
 15. An axle assemblycomprising: a differential carrier; an electric motor module mounted tothe differential carrier, the electric motor module including a motorhousing, a stator that is fixedly disposed in the motor housing, a rotorthat is received in the stator and is rotatable about an axis, and amotor cover that is mounted to the motor housing opposite thedifferential carrier and is spaced apart from the differential carrier,wherein the motor cover contacts the motor housing; and a resolver thatis mounted to a side of the motor cover that faces away from the rotor;wherein a seal carrier plate is received inside the motor cover and isspaced apart from the resolver, wherein the seal carrier plate has aninner surface that is an inside circumference of the seal carrier platethat faces toward and defines a seal carrier plate hole and an outersurface that is an outside circumference of the seal carrier plate thatis radially disposed with respect to the axis and faces away from theseal carrier plate hole, wherein an inner seal extends from the innersurface to a rotor output flange, an outer seal extends from the outersurface to the motor cover and the resolver is axially positionedbetween the seal carrier plate and the motor cover.
 16. The axleassembly of claim 15 wherein the rotor output flange extends into amotor cover opening in the motor cover.
 17. The axle assembly of claim16 further comprising a rotary disc that is mounted to the rotor outputflange, wherein the resolver detects a position of the rotary disc. 18.The axle assembly of claim 15 wherein the seal carrier plate iscompletely received inside the motor cover.
 19. The axle assembly ofclaim 18 wherein the rotor output flange extends into the seal carrierplate hole.
 20. An axle assembly comprising: a differential carrier; anelectric motor module mounted to the differential carrier, the electricmotor module including a motor housing, a stator that is fixedlydisposed in the motor housing, a rotor that is received in the statorand is rotatable about an axis, and a motor cover that is mounted to themotor housing opposite the differential carrier and is spaced apart fromthe differential carrier, wherein the motor cover contacts the motorhousing; and a rotor output flange that is fixedly mounted to the rotor;a resolver that is mounted to a side of the motor cover that faces awayfrom the rotor; wherein a seal carrier plate is mounted to the motorcover and defines: a seal carrier plate hole that extends around theaxis, wherein the rotor output flange is received inside the sealcarrier plate hole; and a seal carrier plate flange that extends aroundthe axis and extends from the seal carrier plate toward the motor coversuch that the seal carrier plate flange does not engage the resolver,the seal carrier plate flange supporting an outer seal that extendsaround the axis and around the seal carrier plate flange and thatextends from the seal carrier plate flange to the motor cover, andsupporting an inner seal that is received inside the seal carrier platehole is spaced apart from and does not engage the seal carrier plateflange, and that extends from the seal carrier plate to the rotor outputflange.